KARACHI, 15 September — US and Pakistani officials were questioning key Al-Qaeda suspect Ramzi Binalshibh yesterday after arresting him on the anniversary of the Sept. 11 attacks he is accused of helping to plan. Pakistan said a second high-level Al-Qaeda suspect was also being held after a series of raids in Karachi this week which netted a total of 12 foreign suspects and left two dead.

Binalshibh, who is wanted by Germany for his alleged role in planning and carrying out the hijacked plane attacks on the United States, is one of the most important Al-Qaeda members to be taken into custody over the past year.

US officials have said the Yemeni national, who was refused a visa into the United States at least four times before Sept. 11, 2001, wanted to join the 19 hijackers involved in last year’s attack.

Pakistan’s Interior Minister Moinuddin Haider said the suspects were with Pakistani intelligence agencies. He said Pakistan was ready to hand the suspects over to US authorities if there was evidence they were involved in terrorist activities. But the German government said it also wanted to try Binalshibh.

“We in Germany have issued an international arrest warrant that we want to enforce,” German Interior Minister Otto Schily told German ARD television in Copenhagen.

A correspondent for the Al-Jazeera satellite station interviewed Binalshibh and another top suspect, Khalid Shaikh Mohammed, in Karachi three months ago. The interview was broadcast this week.

Yesterday, an Arabic language website issued a statement on the arrest, implying that it may have been linked to the Al-Jazeera interview. “The arrest of Binalshibh came a few days after an interview on Al-Jazeera was broadcast,” the statement said. “We would like to indicate that if, God forbid, this news is correct, this means there was a kind of treason that caused brother Ramzi to fall into the hands of those infidels, which requires a warning to all brothers.”