OMAHA, Neb. (AP) — Investigators long suspected two known criminals were responsible for a shooting that killed two Nebraska lawmen in 1937.

But it wasn’t until 80 years later that the case was re-examined when one of the suspect’s sons told investigators he, too, believed his father was responsible.

The Nebraska Attorney General’s Office announced Tuesday investigators consider the case solved after a three-year effort that included tracking down decades-old case files.

The office says evidence shows that the two suspects — Marion Cooley and Charles Doody — shot Boone County Sheriff Lawrence Smoyer and County Constable William Henry Wathen outside a farm near Albion on June 17, 1937.

The lawmen were ambushed while investigating a suspicious vehicle. Smoyer died instantly. Wathen died 108 days later.

Cooley died in 1965, and Doody in 1995.

LINCOLN, Neb. (AP) — Officials say they tightened security and further restricted prisoner movement after discovery of drug use by some inmates at the Nebraska State Penitentiary in Lincoln.

The Correctional Services Department said in a news release Sunday that at least 15 inmates are suspected of using K2, synthetic marijuana.

The prison canceled all Sunday visits and modified operations to more closely control inmate movement.

Department spokeswoman Dawn-Renee Smith says one inmate required outside medical attention Sunday related to the drug use. Smith says investigators are trying to find out how the K2 got into the prison.

LINCOLN, Neb. (AP) — The University of Nebraska Board of Regents is expected to consider a one-year extension that would keep system President Hank Bounds under contract through the 2020-21 school year.

Bounds’ current contract expires June 30, 2020.

The extension doesn’t include any salary increase. Last year regents approved a 6.3 percent increase that took Bounds’ base pay up to $510,400 annually. Bounds also is paid a privately funded supplement of $20,000 a year. He joined the system in 2015.

The board is scheduled to meet Thursday in Lincoln.

The Institute for Supply Management, formerly the Purchasing Management Association, began formally surveying its membership in 1931 to gauge business conditions.

The Creighton Economic Forecasting Group uses the same methodology as the national survey to consult supply managers and business leaders. Creighton University economics professor Ernie Goss oversees the report.

The overall index ranges between 0 and 100. Growth neutral is 50, and a figure greater than 50 indicates an expanding economy over the next three to six months.

Here are the state-by-state results for September:

Arkansas: The September overall index for Arkansas rose to 67.3 last month from August’s 65.9. Components of the index were new orders at 72.9, production or sales at 76.7, delivery lead time at 66.6, inventories at 60.9 and employment at 59.6. “Over the past 12 months, Arkansas increased manufacturing employment by 2.1 percent, or approximately 3,300 manufacturing jobs. Losses for durable-goods producers were more than offset by gains for nondurable-goods manufacturers,” Goss said.

Iowa: The state’s overall index rose to 60.7 in September from 57.7 in August. Components of the index were new orders at 63.2, production or sales at 70.6, delivery lead time at 60.0, employment at 54.3 and inventories at 55.4. “Over the past 12 months, Iowa increased manufacturing employment by only 0.7 percent, or approximately 1,400 manufacturing jobs. Gains were experienced almost equally by durable-goods producers and nondurable-goods manufacturers,” he said.

Kansas: Kansas’ overall index increased to 43.6 last month, a regional low. The August figure was 42.8. Components of the index were new orders at 47.1, production or sales at 52.7, delivery lead time at 40.5, employment at 38.5 and inventories at 39.3. “Over the past 12 months, Kansas experienced a decline in manufacturing employment of 2.1 percent, or approximately 3,300 manufacturing jobs. Almost all of the loss was recorded by the state’s durable-goods manufacturing sector,” said Goss.

Minnesota: The state’s overall index declined to a still healthy 59.4 from August’s 61.8. Components of the overall September index were new orders at 64.3, production or sales at 68.6, delivery lead time at 57.9, inventories at 53.7 and employment at 52.5. “Over the past 12 months, Minnesota increased manufacturing employment by 1 percent, or approximately 3,100 manufacturing jobs. Most of the gains were recorded by nondurable-goods producers,” he said.

Missouri: Missouri’s overall index climbed to 63.9 last month from 61.1 in August. Components of the overall index were new orders at 69.3, production or sales at 69.2, delivery lead time at 66.2, inventories at 60.5 and employment at 54.3. “Over the past 12 months, Missouri increased manufacturing employment by 3.1 percent, or approximately 8,100 manufacturing jobs,” Goss said. Gains were recorded by both durable- and nondurable-goods producers.

Nebraska: The September overall index for Nebraska rose to 59.3 from 57.9 in August. Components of the index were new orders at 65.4, production or sales at 64.2, delivery lead time at 59.0, inventories at 54.6 and employment at 53.4. “Over the past 12 months, Nebraska increased manufacturing employment by only 0.8 percent, or approximately 800 jobs manufacturing jobs. Losses for durable-goods producers were more than offset by gains for nondurable-goods manufacturers,” he said.

North Dakota: North Dakota’s overall index declined to 63.9 from August’s 69.1. Components of the overall index in September were new orders at 70.4, production or sales at 74.3, delivery lead time at 58.5, employment at 57.5 and inventories at 58.8. “Over the past 12 months, North Dakota experienced a 2.8 percent decline in manufacturing employment, or approximately 700 manufacturing jobs. However, additions by the state’s large energy sector more than offset manufacturing losses,” said Goss.

Oklahoma: Oklahoma’s overall index climbed to a healthy 62.7 in September from 56.2 in August. Components of the overall index were new orders at 67.8, production or sales at 71.9, delivery lead time at 61.5, inventories at 56.6 and employment at 55.4. “Over the past 12 months, Oklahoma increased manufacturing employment by 2.8 percent, or approximately 3,600 manufacturing jobs. Contrary to the other eight states, Oklahoma’s gains were driven by the state’s durable-goods manufacturers,” he said.

South Dakota: The state’s overall index improved slightly, hitting 46.6 last month, compared with 45.5 in August. Components of the overall index were new orders at 50.4, production or sales at 55.7, delivery lead time at 43.8, inventories at 42.1 and employment at 41.2. “Over the past 12 months, South Dakota experienced a decline in manufacturing employment of 1 percent, or approximately 400 manufacturing jobs. Almost all of the loss was recorded by the state’s durable-goods manufacturing sector,” Goss said.

LINCOLN, Neb. (AP) — Nebraska’s corrections department is offering new incentives to try to fix employee recruiting challenges and high turnover rates at the state’s two largest prisons.

The Department of Correctional Services is offering a $2,500 signing bonus to the first 100 new employees hired between Monday and Nov. 17 to work at the Tecumseh State Correctional Institution and the Nebraska State Penitentiary.

The department will also pay experience-based merit raises to staff members the Tecumseh prison. Employees with one to three years of service will get a 2.5 percent raise, and the amount will increase up to a 10 percent for employees with more than 10 years of service.

Department officials hope the incentives will help fill open jobs, which could save money by reducing employee overtime costs.

LINCOLN, Neb. (AP) — Gov. Pete Ricketts is planning to tour the state with business leaders and economic development officials after proclaiming October as “Manufacturing Month.”

Ricketts issued the proclamation on Monday with officials from the Department of Economic Development, Nebraska Chamber of Commerce and Industry and the Nebraska Manufacturing Advisory Council. Manufacturing is the state’s second-largest industry, behind agriculture. It employs about 97,000 people.

Ricketts will make stops in Grand Island and Omaha on Tuesday; Sidney and Gering on Thursday; and Alliance, Holdrege Minden and Omaha on Friday.

Scott Volk, a vice president for MetalQuest in Hebron, says one of the greatest challenges manufacturers face is persuading young people to join the industry.

Joseph Young of the Nebraska Chamber says tax reform would also help the state’s manufacturers.

LINCOLN, Neb. (AP) — Nebraska Gov. Pete Ricketts says he doubts the closure of four beer stores on the state border will fix the alcohol-related problems on South Dakota’s Pine Ridge Indian Reservation.

Ricketts said Monday that addressing the issue will likely require action within the reservation, which is home to the Oglala Lakota Nation.

The Nebraska Supreme Court issued a ruling on Friday that upheld a state commission’s decision not to renew the stores’ licenses in the village of Whiteclay. The stores had sold the equivalent of about 3.5 million cans of beer annually in the unincorporated town, despite having nine residents. Before the stores were closed, Whiteclay had served as a hangout for people to loiter.

Ricketts notes that Nebraska’s state government helped pay demolition costs for two abandoned buildings in Whiteclay.