As part of a larger case involving bomb threats made to several Walmart stores in the Kansas City area, the FBI’s Kansas City division is working with Lawrence police investigating bomb threats made to two local Walmart stores Sunday morning, FBI spokeswoman Bridget Patton said. However, Patton said the FBI had no case updates to provide as of Wednesday afternoon.

About 2 a.m. Sunday, a man called 911 and threatened violence with bombs and firearms at both Lawrence Walmart stores, 550 Congressional Drive and 3300 Iowa. Minutes after the Walmart calls, Lawrence Memorial Hospital staff contacted police and reported that a man had made similar threats against the hospital. Police searched the buildings but found nothing dangerous, Sgt. Trent McKinley said.

The Leavenworth Walmart also received a bomb threat Sunday, about 4:30 a.m.

The threats follow a string of false reports last week in Missouri and Oklahoma. The Associated Press reported that stores in eight Missouri communities received similar threats on Friday. A threat shut down a store in Claremore, Okla., on Wednesday.

Attempts to contact Walmart representatives have been unsuccessful.