ISLAMABAD, Pakistan (CNN) -- Pakistani police have arrested two suspects over the assassination of former prime minister and leading opposition figure Benazir Bhutto.
Benazir Bhutto greets her supporters at the rally where she was later killed.
The two suspects, named only as Rafaqat and Hasnain, were arrested in Rawalpindi -- a garrison city outside Islamabad, where Bhutto was killed, the police official said.
No other details on their arrests were immediately available.
Pakistani investigators looking into Bhutto's December 27 killing are being assisted by a small team from Britain's Scotland Yard.
Police are still holding Aitzaz Shah, 15, and a man named Sher Zaman, who were detained last month in Dera Ismail Khan in Pakistan's North-West Frontier Province.
Pakistani officials have been vague on Shan and Zaman's links to Bhutto's killing, and said they have not been named official suspects.
Pakistan's government has concluded that Bhutto's assassination was orchestrated by Baitullah Mehsud, the leader of the Pakistani Taliban who has ties to al Qaeda -- a conclusion that the CIA came to as well.
Bhutto was killed while standing in an moving armored car after rallying supporters for parliamentary elections. The vote, originally scheduled for early January, was postponed until Feb. 18 in the wake of her death.
Her head was above the sunroof and unprotected at the time of the attack.
The cause of her death is not clear: a bomber blew himself up near Bhutto's limousine, and videotape showed a gunman apparently firing shots toward her -- but no autopsy was carried out at the family's request.
Bhutto's family and party have accused Musharraf's government of having a role in her death, and have criticized the security provided to her by the government. Musharraf has denied any involvement in her death. E-mail to a friend