A Brooklyn man was nabbed after he allegedly used a box cutter to slash a store manager’s neck Thursday afternoon, cops said.

The 40-year-old manager asked William Clifton, 21, who was accompanied by a woman, to leave the Family Dollar store on Atlantic Avenue near Ralph Avenue in Brownsville at 2:25 p.m. Clifton refused, sparking an argument, police said.

Clifton took out a box cutter and slashed the right side of the manager’s neck before fleeing west on Atlantic Avenue.

Cops caught up with Clifton and his accomplice at Ralph Avenue and Dean Street. Clifton was charged with assault, criminal trespassing, criminal possession of a weapon, menacing and disorderly conduct. It was not clear whether his accomplice was charged.

The manager is listed in critical but stable condition at Kings County Hospital.