Criticisms mount as Zimbabwe heads towards runoff election

"This is a clear testimony of the callousness of this regime," Tsvangirai said to a funeral procession of hundreds gathered outside the capital city of Harare. "They can kill us. They can maim us. But we are going on the 27th of June, our hearts dripping with blood, to vote him out of office."

Tsvangirai was referring to the date of the runoff election with Mugabe. On Sunday, Tsvangirai was at the funeral of Tonderai Ndira, a senior member of Tsvangirai's Movement for Democratic Change party who was kidnapped and shot to death, according to MDC party members.

MDC members have accused Mugabe supporters of the attack, along with other election-related violence.

A Mugabe Cabinet member has denied that the government had any role in the killing, and said the report was an effort by the MDC to gain international sympathy.

Zimbabwean President Robert Mugabe has threatened to expel the US ambassador, accusing him of meddling in the country's political process.

"I am just waiting to see if he makes one more step wrong. He will get out," Mr Mugabe told a rally in Harare.

Earlier this month ambassador James McGee warned post-election violence in Zimbabwe was "spinning out of control".

Earlier this month, Mr McGee told the BBC he had found evidence of "politically-inspired" violence against hundreds of people in Zimbabwe.

The diplomat warned the situation made it impossible for the second vote to be fair.

Mr Mugabe also noted that Mr McGee had publicly urged opposition Movement for Democratic Change (MDC) leader Morgan Tsvangirai to return to Zimbabwe to lead his embattled supporters in the run-off.

"As long as he carries on doing that, I will kick him out of the country," Mugabe said of Mr McGee, a Vietnam War veteran.

"I don't care if he fought in Vietnam. This is Zimbabwe, not an extension of America," he said.