KARACHI - TENS of thousands of Pakistanis massed Friday at the tomb of slain former premier Benazir Bhutto, one day before ceremonies to mark the first anniversary of her assassination, a party official said.

More than 35,000 people had already arrived in the rural southern town of Garhi Khuda Bakhsh ahead of Saturday's ceremonies at the Bhutto family mausoleum there, Pakistan People's Party (PPP) spokesman Ijaz Durrani told AFP.

People were travelling by train, bus, car, bicycle and even on foot to reach the site, he said. Hundreds of thousands were expected to arrive by Saturday.

MS Bhutto, 54, was killed on Dec 27, 2007 in a gun and suicide attack at an election rally in the garrison city of Rawalpindi, just two months after returning to Pakistan from exile.

Pakistani President Asif Ali Zardari, Ms Bhutto's widower, and her son Bilawal Bhutto Zardari, who co-chairs the PPP with his father, were expected to lead the procession of mourners on Saturday.

About 8,000 police, paramilitary rangers, party workers and volunteers have fanned out across the town to protect Mr Zardari, his son, Prime Minister Yousuf Raza Gilani and other dignitaries expected to attend, the PPP spokesman said.

The town was full of people carrying portraits of Ms Bhutto, and vendors were doing a brisk business in Bhutto memorabilia, selling posters and CD recordings of her speeches.

Mr Zardari has ordered local officials to arrange for meals for the mourners, Mr Durrani said.

The government has declared Saturday a national holiday in honour of the charismatic Ms Bhutto, the first woman to lead a Muslim nation.

Her killing shocked the world, and threw the world's only nuclear-armed Islamic nation into chaos, sparking violence and leading to months of political turmoil that ended in September when Mr Zardari claimed the presidency.

The home minister of southern Sindh province, Zulfiqar Mirza, has warned of the possibility of violence linked to the Bhutto commemorations, but provincial spokesman Waqar Mehdi said authorities had taken appropriate steps.

A special security wall has been erected around the mausoleum as part of a raft of precautions taken to safeguard Mr Zardari. -- AFP