JOHNSTON, Iowa (WHO) — Investigators are working to determine who is behind bomb threats called into multiple Hy-Vee locations across the Midwest, including in Johnston and Ames.

Police in Johnston were called to the Hy-Vee at 5750 Merle Hay Road around 7:30 Monday night after receiving a report of a bomb threat, according to Janet Wilwerding, Communications Manager for the City of Johnston.

The store was evacuated and a bomb sweep was performed. Police found the threat was not credible and employees and customers were allowed back in to the store around 8:00 p.m.

Wilwerding said the caller was a male with a foreign accent.

Sgt. Amber Christian with the Ames Police Department told WHO 13 a call came in to police around 7:11 p.m. Monday from a manager at the Hy-Vee at 3800 Lincoln Way. The manager said they’d received a call from a man claiming he had hidden a pipe bomb in an aisle at the store.

The store was evacuated and police did a visual sweep but did not locate a bomb. People were let back into the store just before 8:00 p.m.

The manager told investigators the caller did not have a noticeable accent.

Sgt. Christian said similar threats were made to Hy-Vee locations in South Dakota and Minnesota, as well as other stores in Iowa in communities like Council Bluffs and Sioux City.

Hy-Vee provided a statement to WHO 13 Tuesday morning about the incident:

“You may have seen in the news that there have been some recent bomb threats called in to Hy-Vee locations. Unfortunately, this type of activity is taking place all across the industry and nation.  Retailers such as Walmart, Target, Kroger, Whole Foods, Harris Teeter and Publix, along with others, have also been a target of these threats. In the majority of these instances, the callers are specific with an ask and issue the threat of a bomb if their request is not met.

We take each of these calls very seriously in order to protect the safety of our employees and customers. In each case, our security team partners with law enforcement, such as the FBI and local law enforcement, and follows their guidance in response to the threat. If this activity persists, we will continue to take each threat seriously and continue to act in the best interest of the safety of our employees and customers.”

Hy-Vee