GARDEN GROVE (CBSLA.com/AP) — A Southland man who was the first American charged with treason in over half a century for joining the Al-Qaida terror network was among those killed in a U.S. strike earlier this year, according to officials.

Adam Gadahn, who was charged in 2006 for providing “aid and comfort” to Al-Qaida, was killed in a U.S. military operation in January, President Obama announced Thursday.

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President Obama said he takes “full responsibility” for a U.S. counterterrorism mission that inadvertently killed an American and an Italian held hostage by al-Qaida. He defended the legality of the January drone strike against an al-Qaida compound and said there had been no information suggesting the hostages were at that location.

Among the al-Qaida operatives believed killed in the strike was American Ahmed Farouq, who the White House says was an al-Qaida leader. U.S. officials have also concluded that Gadahn was killed in a separate operation.

The president made no mention of Farouq and Gadahn. Instead, he focused his remarks on American Warren Weinstein, who had been held by al-Qaida since 2011, and Italian Giovanni Lo Porto, who had been held since 2012.

Obama expressed regret for the deaths of the two men and offered his “grief and condolences” to their families.

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“I realize there are no words that can ever equal their loss,” said Obama.

Gadahn grew up on a goat farm in Riverside County and converted to Islam at a mosque in nearby Orange County, according to CBS News.

He reportedly worshiped at the Islamic Society of Orange County in 1997 before being expelled for attacking one of its leaders, CBS News reported.

His mother last spoke to him by phone in March 2001. At the time he was in Pakistan, working at a newspaper, and his wife was getting ready to have a child, according to CBS News.

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