ISLAMABAD — Pakistan’s election commission said today that unrest following the killing of Benazir Bhutto would almost certainly force the postponement of January 8 elections, despite opposition threats of street protests if the poll is delayed.

As election officials met with political leaders to discuss a possible delay, an aide to Bhutto said the opposition leader had been planning to give two American lawmakers a report accusing the ruling regime of working to rig the vote when she was killed Thursday.

Government and election officials earlier said they expect a delay of up to six weeks in the polls, which are seen as key to restoring democracy to this nuclear armed American ally.

A lawmaker from Bhutto’s Pakistan Peoples Party, Senator Latif Khosa, said he did not know if her killing was linked to the 160-page report she was to give to Senator Specter of Pennsylvania and Rep. Patrick Kennedy of Rhode Island at a meeting scheduled for a few hours after she was killed.

The file outlined several instances of electoral interference, including one case where a major from the intelligence services sat with an election official when the official rejected the nomination papers of Peoples Party candidates, Mr. Khosa said.

Another official stopped a candidate from filing his nomination in the southwestern Baluchistan province, he said.

“The elections were to be thoroughly rigged, and the king’s party was to benefit in the electoral process,” he said, referring to the Pakistan Muslim League-Q party, which is allied with President Musharraf.

Bhutto had repeatedly accused the government of rigging the vote, but rejected boycott calls by other opposition groups, saying she did not want leave the field open for Mr. Musharraf’s loyalists.

Bhutto’s killing last week thrust the country into crisis and triggered nationwide riots that killed 58 people and caused tens of millions of dollars in damage to homes, government offices, and transport facilities. The violence has died down since Sunday amid a heavy police and army presence. Bhutto’s home province of Sindh was especially hard hit.

Opposition groups have demanded the elections proceed as scheduled, anticipating that sympathy votes and anger at Mr. Musharraf would lead to large electoral gains.

However, an election commission spokesman, Kanwar Dilshad, said it now “looks impossible” to hold the polls on January 8.

“Our offices in 10 districts of Sindh have been burned, the electoral rolls have been burned, the polling schemes, the nomination papers have been burned,” he said. “We are in a very tricky situation.”

The commission said it would announce a final decision tomorrow after meeting Pakistan’s political parties.

A former prime minister, Nawaz Sharif, leader of another opposition party, threatened street protests if the vote was delayed. “We will agitate,” Mr. Sharif said yesterday. “We will not accept this postponement.”

Bhutto’s party, now led by her husband and son, accused Mr. Musharraf of wanting to delay the polls to allow public anger over her death to evaporate.

“There have been elections in conflict zones such as Iraq and Afghanistan so I find it difficult to understand why this election cannot be held on time,” a spokesman for Bhutto’s party, Sherry Rehman, told Dawn TV.

Britain and America were also eager for the vote to take place as scheduled, but have indicated they would accept a slight delay if technical reasons dictated one.

“The key here is that there be a date certain for elections,” a spokesman for the State Department, Tom Casey, said yesterday. “We would certainly have concerns about some sort of indefinite postponement of the elections.

Bhutto was killed in a gun and suicide bomb attack that the government blamed on Islamic extremists.