Derek Alvez Police remained in front of Espana restaurant in Annadale yesterday, as the investigation into the fatal stabbing continues. What should have been the happiest of occasions -- a celebration of a young man's engagement -- ended in horror when the groom-to-be was brutally stabbed to death in a sidewalk brawl outside an Annadale restaurant early yesterday morning. As of last night, the suspect had not been apprehended. Police sources say the suspect in the case is a white male in his 30s, approximately 6 feet, 2 inches tall, with blond hair and a light complexion. The victim, 27-year-old Antonio Lacertosa of Huguenot, had celebrated his engagement earlier in the evening with his fiancee, family and friends at a South Shore catering hall, but he and some friends wanted to continue the party, so they ended up at Espana Restaurant at 833 Annadale Rd. The law enforcement source, who is not authorized to speak to the press, told the Advance that Lacertosa and his friends got into a dispute with Espana management over rowdy behavior inside the bar at approximately 2 a.m. Lacertosa and his buddies then got into a "scrum" outside, and a restaurant worker emerged from the restaurant with a "butcher-type knife" and stabbed Lacertosa in the torso, mortally wounding him, the police source told the Advance.