YAPHANK - It took police 72 hours to make arrests in the Medford pharmacy killings, and they say they have the public to thank for that.Immediately after Suffolk County police released surveillance video from Haven Drugs in Medford, they say tips starting pouring into Crime Stoppers, totaling more than 430. Police say those tips were one of the most important elements that led to the arrests of David Laffer and his wife in Medford yesterday. "We do know we received some extremely important tips that were passed on to the homicide bureau, which helped solve this case," says Lt. Bob Donohue, of the Suffolk Community Outreach Bureau.While following tips, police also searched the pistol license database. That is how they discovered that Laffer had a registered .45 caliber gun that matched the murder weapon, police say.County Executive Steve Levy (R-Suffolk) says another clue that led police to Laffer was that his name was on a list of pharmacy customers who had received various drugs in the past. In court today, Chief Prosecutor John Collins revealed that police also found Laffer's fingerprints on a piece of paper inside the pharmacy.Continuing coverage: Medford pharmacy massacreCops: Husband, wife arrested in Medford drug-store massacre