A drug deal gone bad inside a Center City McDonald’s led to a fight and stabbing that injured four people, police said.

On Sunday around 6 p.m., two 18-year-old men as well as a 21-year-old man were inside the McDonald’s restaurant on Broad and Arch streets. While inside, one of the 18-year-olds was buying drugs from a 56-year-old man, police said. The 18-year-old handed the man the money but then changed his mind and decided he wanted his money back, according to investigators.

Police say the 56-year-old left the McDonald’s with the money however and the teen followed him outside before confronting him on the 1300 block of Arch Street.

The 56-year-old then gave the 18-year-old his money back and the teen walked away, police said. As the 56-year-old walked away, the two 18-year-olds and the 21-year-old confronted him again and began fighting him, according to investigators.

The 56-year-old then pulled out a knife and began swinging, cutting the two teens and the 21-year-old. One of the 18-year-olds suffered a laceration to his nose. The second 18-year-old was cut on his right hand. Finally, the 21-year-old suffered a minor laceration on his chest. The two teens were treated at Hahnemann Hospital and later released. The 21-year-old man did not receive any medical treatment.

The 56-year-old man was also taken to Jefferson Hospital where he was treated for injuries he suffered during the fight. The man was taken into custody but later released pending further investigation. So far no charges have been filed.

It was the third reported stabbing incident in Philadelphia Sunday. Early Sunday morning a man was stabbed and killed in the Rittenhouse Square area. A homeless veteran was later arrested in connection to the stabbing. Late Sunday morning a 52-year-old man was stabbed inside a North Philadelphia house. He's currently in critical condition.