Police believe a dispute between two bikie gangs is behind four out of five shooting attacks on Sydney homes and businesses overnight. They have formed a strike force to investigate the attacks, which they say are part of a turf war between the Nomads and Hells Angels clubs. Officers say two homes targeted belong to family members of Hells Angels club members. In the first shooting of the night a man heard shots outside his home at Granville around midnight. But he did not report the shots to police until he found bullet holes in the front of the house at about 6:30am (AEST). Police say the home is owned by family of senior Hells Angels bikie Mahmoud Dib. Shots were then fired into a Baulkham Hills tattoo shop, Tattoo World, about an hour after the Granville attack. Police say a man wearing dark clothing and a black balaclava was seen running away from the shop. No-one was inside the business at the time. Bullets were next fired into the Merrylands home of the parents of senior Hells Angel Jeffrey Sahyoun at about 2:40am. The shots penetrated the kitchen of the home, but three elderly residents inside were not injured. Police have confirmed the occupants included the parents of Sahyoun, who is currently in jail on unrelated charges. Another empty tattoo shop, Infamous Ink, was attacked in Merrylands shortly before 4:30am. Assistant Police Commissioner Frank Mennilli has told 702 ABC Sydney the shootings are cowardly. "This is where we have just individuals who've got a total disregard for the law of this state and its community," he said. "I can assure you and I can assure the community and your listeners these people just better be ready, because we'll be knocking on their door very shortly. "They're cowards who try to display their bravado by firing shots at roller shutter doors or cars or houses. "It's not the first time those particular businesses have been targeted and we know that they have been targeted in the past and they were never reported. "We know who are linked to those businesses and we are targeting them." Police say the fifth shooting is not linked to the others, but was the result of a business dispute. Seven people, including five children, escaped injury when their home in Northmead was shot at just after 1:00am. Three bullet holes could be seen in the windows and balcony door of a bedroom and rumpus room of the two-storey house on Centenary Avenue. A couple have told police their five children, aged between three and 14, were playing on a computer in the rumpus room at the time. At least two bullets narrowly missed the children as they lodged in the ceiling, and police say it is extremely lucky no-one was hurt. A cousin of the children, Sharif Barez, was among a group of relatives who arrived at the home early this morning to check on the family. "I'm relieved that they're safe. It's the repercussions that really still bother me in a sense, they're going to be living through this for a while," he said. 'It could be worse' The city has been in the grip of a wave of gun crime, with dozens of attacks this year alone. New crime figures have confirmed the increase in drive-by shootings is real and not perceived. Data from the state's Bureau of Crime Statistics and Research shows the number of incidents has risen by 41 per cent in the past two years. But the bureau's director, Don Weatherburn, says Sydney has seen worse periods for gun crime. "The increase in shootings is obviously a matter of real concern, but... the number of shooting incidents is still way below its peak in 2002," he said. "We've seen an upswing in the last two years, but there's a long way to go before we're back to where we were in 2002."