Officials said polling had gone slowly because voters were unaccustomed to paper balloting, which was being tried for the first time.

The Botswana Democratic Party is widely expected to win again

Since gaining independence from the UK in 1966, Botswana has been governed by the Botswana Democratic Party led by President Festus Mogae.

It will be his first popular test since taking over in March following the retirement of President Masire.

With the opposition divided between three parties, correspondents say the BDP is again expected to win a majority in the 40-seat Assembly.

"We are going to win, of course," Mr Mogae told reporters after casting his vote in the capital, Gaborone.

Aids epidemic

Correspondents say the Aids epidemic and the country's 20% unemployment rate are two of the most serious issues the new government will be expected to tackle

Nearly one fifth of the population is thought to be infected with HIV, and the crisis has slashed the average life expectancy to 40.

Botswana is widely regarded as a model African democracy

Many voters are also angry over the government's failure to distribute some of the riches from Botswana's massive diamond wealth to the population.

Diamonds have given the country foreign exchange reserves of $5.6bn, but 40% of Botswanans live in poverty.

Saturday's poll is the eighth to take place in independent Botswana - southern Africa's oldest democracy - but it is the first to use a ballot paper system.

Earlier polls have used coloured disks representing the different parties which voters dropped into the ballot boxes.

Voter apathy

Politicians from all sides have expressed concern about apparent voter apathy after decades of rule by the same party.

Electoral officials say they estimate that only 58% of more than 800,000 Bostwanans eligible to vote have registered to do so - a level unchanged from the last poll in 1994 election and down sharply from 72% in 1989.

Last month, President Mogae was forced to declare a state of emergency in order to recall parliament to pass a law allowing 60,000 potential voters to take part in the election.

They were disqualified after a writ for the elections was issued before the full voters roll had been completed.