the suspect is in custody

() — Philadelphia police investigate a sprawling shootout which is believed to have left five dead and two children wounded Monday night, before authorities arrested a suspect who they say had a bulletproof vest, an AR-15-style rifle and a handgun.

Authorities initially said four people were dead, but announced the discovery of a fifth body in the same southwest Philadelphia neighborhood of Kingsessing early Tuesday morning, saying they preliminarily believe that person died on the same spree.

The shooting spanned several blocks, damaging vehicles and littering the streets with dozens of bullet casings, Philadelphia Police Commissioner Danielle M. Outlaw said at a news conference Monday night.

Authorities have yet to identify the suspect; Outlaw said he believed he was 40 years old.

When officers arrested the suspect after a foot pursuit, he was wearing a bulletproof vest stocked with multiple ammunition clips and was carrying both pistols and a scanner, according to the commissioner.

Authorities have “absolutely no idea” why the shooting occurred and have yet to find any connection between the victims and the suspect, Outlaw said.

“We are investigating the area to get everything we can: identify witnesses, identify where the cameras are located, and do everything we can to find out the ‘why’ behind it,” he said.

The shooting in Philadelphia erupted Monday night as the United States suffers from a seemingly endless epidemic of gun violence: There were at least six mass shootings in the first three days of July, according to the Gun Violence Archive, including another this Monday night in Fort Worth, Texas, that left at least three dead and eight injured. Another shooting in Baltimore on Saturday left two dead and 28 wounded.

These were some of at least 341 mass shootings in the US so far this year, according to the file, which, like , defines a mass shooting as one in which four or more are shot. people, not including the shooter.

Police work at the scene of a mass shooting Monday in the Kingsessing neighborhood of Philadelphia. (Credit: Tracie Van Auken/EPA-EFE/Shutterstock)

“This devastating violence must stop,” said Philadelphia Mayor Jim Kenney, in a tweet this Monday night.

“My heart goes out to the loved ones and families of everyone involved, and I send my prayers to the victims,” ​​Kenney said.

Of the four murder victims that police initially learned of, three were men ages 20, 22 and 59. The fourth was also a man, but investigators did not know how old he was, Outlaw said.

The fifth victim was a 31-year-old man, said city Police Chief Inspector Scott Small. He was discovered early Tuesday hours after the other victims were found at a home in Kingsessing, a neighborhood that sits on the west bank of the Schuylkill River in southwest Philadelphia.

Outlaw described the conditions of the injured boys, ages 2 and 13, as stable.

A second person was also in custody Monday night, someone authorities believe may have returned fire, Outlaw said.

This is how the shooting in Philadelphia unfolded

Police officers arrived at the area where the shooting began around 8:30 p.m. Monday, Outlaw said, describing multiple gunshot victims.

“As the victims were being treated and prepared for transport to the hospital, they also heard multiple gunshots in the street,” Outlaw said.

Again, as officers responded to the second scene of the shooting, more shots were heard on a nearby street, he said.

Officers found the suspect and gave chase on foot as he continued to fire, Outlaw said. The suspect was eventually cornered in an alley and taken into custody, he said.

“Thank God our officers were here on the scene (and) responded as quickly as they did,” Outlaw said Monday. “I can’t even describe the level of bravery and courage that was shown.”

The body of the murdered 31-year-old man was found at around 12:30am Tuesday by his father in the sitting room of a Kingsessing house, according to Small, the chief inspector.

The father reported this to an officer who was in the area investigating the shooting hours earlier. The man had been shot multiple times and was pronounced dead shortly after by responding medics, Small said.

Investigators found seven rifle bullets inside the home, Small said. Due to the location of the home and ballistic evidence, investigators believe that person’s death is related to the others, Small said.

“We believe this is now the seventh (person shot) and will be the fifth person that has been shot and killed,” Small said.

— ‘s Jason Hanna, Christine Sever, Danny Freeman and Sara Smart contributed to this report.