At least four people were shot outside the Nationals Park stadium in Washington D.C., leading to the suspension of a baseball game.

“A shooting has been reported outside of the Third Base Gate at Nationals Park,” the Washington Nationals tweeted at 9.47 p.m. on Saturday night, adding that the fans were encouraged to exit the stadium.

The game between the San Diego Padres and Washington was suspended in the sixth inning Saturday night after a shooting outside Nationals Park that caused echoes of gunfire inside the stadium and prompted fans to scramble for safety in the dugout.

One of the victims was a woman who was attending the game and who was struck while she was outside the stadium, he said. Her injuries weren’t considered life-threatening.

Two people who were in one of the cars later walked into a local hospital with gunshot wounds and were being questioned by investigators. Investigators were still trying to locate the second vehicle involved in the shooting.

The gunshots caused panic among fans inside the stadium, some of whom ducked for cover, hiding underneath tables and behind seats as announcers warned people to stay inside the park.

“We heard what sounded like rapid gunfire. We didn’t know where it was coming from,” umpire crew chief Mark Carlson said.

Fans sitting in left field quickly began leaving through the center field gate. A short time later, fans along the first base side began briskly leaving their seats.

Some fans crowded into the Padres’ dugout on the third base side for cover, while sirens could be heard from outside the park.

Ted Borenstein, 26, was at the game with his girlfriend and his best friend, celebrating her birthday and “having a great time” when he heard two pops. He said the group thought it was practice for a fireworks show.

Borenstein said he quickly realized it was far more serious when he saw people in the stands start filing out and watched Padres star shortstop Fernando Tatis Jr. “bolt from the field.”

In the stadium’s Diamond Club, where he and his friends were, people were hiding under tables and chairs, thinking there was a shooter inside the stadium.

“People were down on the ground, kind of petrified, trying to calm down the younger kids,” he said.

“I was taken aback, I was scared,” he said.

More than two dozen police cars, ambulances and fire engines were on the street outside the third base side of the stadium and a police helicopter hovered overhead.

Arman Ramnath, 27, from nearby Arlington, Virginia, and a recent law school graduate, said he and a friend were sitting in the third base side of the Nationals Park when they heard what sounded like fireworks.

“We weren’t sure what it was. Then everyone started ducking,” Ramnath said.

Ramnath said he and his friend ended hiding behind the seats for five or more minutes.

“It felt very surreal. I wasn’t really sure how to react,” Ramnath said. “I mean, you hear about it … but you never expect it to be something that could affect you.”

Police had initially said they believed one of the victims worked at the stadium, but that was not the case.

The Metropolitan Police Department of the District of Columbia (MPDC) said in a tweet shortly afterward that it was “responding to a shooting in the 1500 block of South Capitol Street, SW, in which two people were shot outside of Nationals Park. This is currently an active investigation and it appears there is no ongoing threat at this time”, Xinhua news agency reported.

The MPDC said later in an update that two additional victims associated with the incident walked into area hospitals for treatment of gunshot wounds.

The game was eventually suspended as a result of the incident, police said.