Two investigations by Atlantic City Vice detectives led to four arrests, along with the recovery of drugs and a gun Wednesday, according to police. In one case, Atlantic City police officers seized 51 bags of heroin and 36 bags of cocaine at a home on the first block of North Montpelier Avenue at about 2:30 a.m., following an investigation by Detective William Warner, Lt. James Sarkos said. Cheily Varela, 28, was charged with several drug offenses, including possession with intent to distribute within 1,000 feet of a school. She was also charged with possession of hollow-point ammunition. No gun was recovered in that investigation. She was held at the Atlantic County Justice Facility on $245,000 bail. About three minutes later, officers served a search warrant in the 100 block of North Tennessee Avenue following an investigation by Detective Howard Mason. In addition to heroin and drug paraphernalia, police said they found a loaded 9 mm semiautomatic handgun. Three Atlantic City men were arrested: Michael Mack, 22, Quan Howard, 20, and Amir Hardy, 21. They were charged with drug offenses and possession of the gun and ammunition. Bail had not yet been set. Police said both Mack and Howard previously served prison sentences for gun possession. Mack, whose conviction also included a drug charge, was released the previous February after serving 18 months in prison. Howard was released the previous January after serving two years.