BUENA, N.J. — He was raised in New Jersey, where he was on the high school wrestling team and earned a black belt in karate. Nearly a decade later, Sharif Mobley is under arrest in Yemen, suspected of being an al-Qaida member and accused of killing a guard in an attempt to break out of a hospital. While some acquaintances were startled by the news out of the Middle East on Thursday, a former classmate said that Mobley had strong religious views in high school, often trying to convert friends to Islam, and became increasingly radical, especially after they graduated in 2002.