2 dead, 2 in critical condition after lightning strike near White House

Two Wisconsin residents have died following a lightning strike near the White House on Thursday night, police confirmed to ABC News Friday.

Police said 76-year-old James Mueller and 75-year-old Donna Mueller, both from Janesville, Wisconsin, died after being injured in the strike in Lafayette Park in front of the White House.

Thursday night, D.C. Fire and EMS said it had responded and was treating four patients that were found in "the vicinity of a tree."

It said the two men and two women were transported to area hospitals with "life-threatening injuries."

Officials said it's still unclear what the adults were doing prior to the lightning strike, if they knew each other and why they were in the park.

White House press secretary Karine Jean-Pierre expressed sadness following word the two Wisconsin residents had died.

"We are saddened by the tragic loss of life after the lightning strike in Lafayette Park. Our hearts are with the families who lost loved ones, and we are praying for those still fighting for their lives," she said in a brief statement.

Uniformed U.S. Park Police officers and members of the Secret Service were also on the scene and immediately rendered aid to the victims, an EMS official said during a news conference.

Washington Mayor Muriel Bowser was expected to speak more about the incident at a news conference later Friday morning.

The National Weather Service had issued a severe thunderstorm warning for the area Thursday evening.

ABC News' Beatrice Peterson and Molly Nagle contributed to this report.