A 16-year-old boy had to get 50 stitches in his face after he was beat up, slashed and stabbed by a group of men during an attack inside a Harlem park, police and sources said.

The teen was walking inside Marcus Garvey Park when the suspects approached him and demanded his phone around 4:45 p.m. Wednesday.

The group then proceeded to punch the victim in the head before one of the men pulled out a knife, slashed his face and stabbed him in the lower back, police said. A police source said the teen had to have 50 stitches in his face.

The thieves then took his phone and fled the park.

The teen was rushed to Harlem Hospital in serious but stable condition.