Thousands of people gathered Thursday at the tomb of Pakistani opposition leader and former prime minister Benazir Bhutto to mark the end of the 40-day mourning period for her death.

Ms. Bhutto's husband Asif Ali Zardari addressed the crowd outside the family's mausoleum at Garhi Khuda Baksh in Sindh province, saying his wife's "martyrdom" will be avenged in a democratic way.

Ms. Bhutto's Pakistan People's Party, now led by Zardari, is set to resume campaigning for the country's crucial February 18 elections.

Ms. Bhutto was assassinated in a gun and suicide bomb attack on December 27 in Rawalpindi as she was leaving a political rally. The Pakistani government says she was killed by al-Qaida-linked militants.

Her family and party supporters blame the government and point to the lack of security given to Ms. Bhutto during her campaign.

Police arrested two more suspects today in connection with the killing. Authorities say they are being interrogated.

Pakistani security officials say the two alleged terrorists, identified only as Hasnain and Rafaqat, were detained in Rawalpindi.

In other news, three British investigators from Scotland Yard have returned to Pakistan. The team on Friday is expected to release the findings of its probe into how Ms. Bhutto died.

Some information for this report provided by AFP.