Harare- A sudden crackdown by President Robert Mugabe's security apparatus in the last 24 hours has indicated that he is determined to hold a second-round presidential election against opposition leader Morgan Tsvangirai.

It also suggests he is about to revive rigging mechanisms used in previous elections to ensure victory, according to reports and a wide variety of sources in the diplomatic and civic community.

Mugabe was meeting Friday with the politburo of his Zanu-PF party, reportedly to discuss going into a second round.

The talks took place amid indications that neither he nor Movement for Democratic Change (MDC) leader Tsvangirai would win more than the 50 per cent of votes from Saturday's election needed for an outright victory.

After four days of silence from the government, shadowy intruders ransacked MDC offices, while police arrested two foreign journalists on charges of working "illegally" in Zimbabwe, along with a member of a U. S. think-tank, the National Democratic Institute.

Sources in the northern town of Bindura also reported that members of Mugabe's defeated Zanu-PF party's youth militia were mobilizing, while in the nearby town of Shamva, sources reported people gathering in groups of more than five were being arrested.

In the capital Harare, a column of about 400 men in their 20s and 30s in poor, worn clothing and rucksacks was marched through the centre of town with a police escort.

"They look like war veterans," said an onlooker, referring to the militia used by Mugabe in previous elections to terrorize opposition supporters. Official comments could not be obtained.

Six days after the critical elections, the state Zimbabwe Electoral Commission (ZEC) has still not announced the results of the presidential poll, although electoral experts say that the ballots have already been counted and collated in constituency centres nationwide.

The same experts say it should take no more than a day to pull them together into the total number of votes for each of the three candidates - Mugabe, Tsvangirai and Simba Makoni, Mugabe's former finance minister who abandoned the ruling party in February to challenge his former mentor.

Zimbabweans had to wait through four days of drip-fed announcements before they learned that the opposition won the House of Assembly (lower house of parliament) vote with 109 seats against Zanu-PF's 97.

Observers believe that Mugabe has ordered the ZEC to delay the results to give him time to manipulate his way out of the next challenge - the presidential vote and the likely second round run- off.

The MDC claimed on Wednesday that from its own tally of votes collected from polling stations, Tsvangirai won 50.3 per cent against Mugabe's 43.8 per cent and should be declared the winner, although scrutiny of their figures shows the pro-democracy leader's percentage was 49.1.

A rigorous random sampling by the respected local election watchdog, the Zimbabwe Election Support Network, gave Tsvangirai 49.4 and Mugabe 41.8.

In the parliamentary election, although Tsvangirai's MDC faction took more seats, Zanu-PF more of the total votes cast with 45.9 per cent.

However, observers say that the extra votes for Zanu-PF cannot be translated into votes for Mugabe in a possible second round.

Election observers say they noted that a large number of people who voted for Zanu-PF in the parliamentary vote did not vote for Mugabe in the presidential ballot.

Heavily stacked against Mugabe are those who voted for Makoni, who formed a pact with the smaller faction of the MDC led by robotics professor Arthur Mutambara.

"The natural choice for these voters is Tsvangirai," said an official with a private election watchdog.

The usually well-informed weekly Zimbabwe Independent reported Friday that Mugabe was considering issuing an edict that would replace the three-week period between the first and second rounds required by the constitution, with a three-month hiatus.

"That will give him all that time to abolish the reformed laws that made last week's elections relatively transparent and difficult to rig, and to carry out a real Zanu-PR-style election, with violent intimidation and outright rigging," said a Western diplomat.

"It looks as if he's already started," the diplomat added. (dpa)