A 48-YEAR old Co. Tyrone man living in Philadelphia is in federal custody since Friday, June 27 after being arrested for charges relating to weapons and immigration.Sean O'Neill, a developer and former owner of Maggie O'Neill's Irish bar in Upper Darby, Philadelphia, was arrested when federal agents called to his home, built on a 10-acre property in Chester County, at 6 a.m. on the 27th.The arrest team included agents from the bureau of Alcohol, Tobacco, Firearms and Explosives, Immigration and Customs Enforcement, and Pennsylvania State Police.O'Neill, who arrived in the U.S. on a visitor's visa in 1983, was charged with fraudulently obtaining a green card, making false statements and illegally possessing a silencer.Authorities allege O'Neill, a native of Coalisland, Co. Tyrone, failed to disclose a 1977 conviction accusing him of being a member the Fianna na h'Eireann, an organization with close ties to the Irish Republican Army, when applying for his green card in 1985. Vincent DiFabio, one of O'Neill's two attorneys, (the other is Kirk V. Wiedemer, a immigration lawyer) told a judge at a bail hearing on Wednesday, July 2, that his client disputes any involvement or conviction related to the group.Assistant U.S. Attorney Faithe Taylor challenged DiFabio's statement in court last week, stating that federal agents confiscated a certified copy of O'Neill's conviction when they raided his home.O'Neill's 19-year-old son, Sean Junior, was just released from detention after serving nine-months in a juvenile facility in western Pennsylvania for shooting dead his friend, 17-year-old Scott Sheridan, in 2006. According to court documents, the friends, both classmates, had spent the day together drinking on September 1. Later that evening, back at O'Neill's home, the younger O'Neill pointed his father's .45-caliber, laser-equipped firearm at his friend and it went off, killing Sheridan. His father was at the Jersey Shore when the incident took place.Sean Junior was released on June 25. Two days later his father was arrested.DiFabio described his client as a successful builder and active community member."He is a productive member of society," said DiFabio.He also described in detail major projects O'Neill has currently under construction in Philadelphia, Media and New Jersey."Walking away from them would cost O'Neill millions," DiFabio said.However, U.S. Magistrate Judge Carol Sandra Moore Wells declined to award O'Neill bail."This is a matter of security more so than anything else," Wells told a courtroom full of O'Neill's friends and family, including his wife, two daughters and his son.On the weapons charge, authorities allege that O'Neill purchased four firearms between 1983 and 1997, providing false information about his birth date on each purchase form.Taylor told the judge about a silencer manufactured in London with no serial number, another item resembling a similar silencer that has yet to be tested, and a book called How to Make Disposable Silencers, that were all recovered from O'Neill's home. She stated that O'Neill was a danger to the community.DiFabio said that O'Neill used the "so-called silencer" to kill squirrels and rabbits on his property.Taylor also told the judge that O'Neill had business dealings and bank accounts in Northern Ireland describing them as "a safe haven." DiFabio defended his client's accounts and said there was nothing "sinister" about O'Neill's development dealings in Ireland.Taylor also said O'Neill lied about the date of his last trip to Ireland.DiFabio and Wiedemer said they will appeal the ruling.If convicted O'Neill faces up to 57 months in prison and immediate deportation after his sentence is served.