Officials say Brookfield Zoo visitors were forced to shelter for hours after the threat

Brookfield Zoo received a “potential threat” on Tuesday, forcing visitors into a shelter-in-place for several hours.

Visitors and staff safely exited Brookfield Zoo after being asked to shelter in place Tuesday afternoon while officials investigated a potential threat.

According to Brookfield Zoo’s official Twitter account at 8:10 p.m., all visitors and staff were safely released from the zoo

Around 8:10 a.m. zoo officials and Brookfield police gave the “all-clear.”

In a tweet at approximately 6 p.m. Tuesday, the zoo asked people to stay sheltered inside the facility until officials cleared the scene “out of an abundance of caution.”

“The is working with Brookfield Zoo Police to investigate the situation throughout the park and surrounding area actively… 

We ask that guest’s on-site shelter be in place until law enforcement gives the all-clear,” the zoo said in a statement. Officials Posted on Twitter.

According to Brookfield Zoo Police Chief Mike Pendola, at approximately 5:15 p.m., 911 dispatchers received a call from the crisis-intervention line

Information from the call was described as “vague” but authorities instituted a lockdown