A government statement said Mr Tobback had not committed any personal errors and asked him to stay in his post.

Asylum-seeker Semira Adamu, 20, died on Tuesday after police officers travelling with her on a flight to Togo tried to restrain her by putting a pillow over her mouth.

Louis Tobback said he took full responsibility

Mr Tobback, who is also the vice prime minister, has only been in his post for five months. He submitted his resignation to Prime Minister Jean-Luc Dehaene on Thursday.

Belgium has suspended the deportation of asylum-seekers following Ms Adamu's death.

Officers charged

Two police officers have been charged with assault for covering the woman's face as they tried to put her on board the plane on Tuesday.

As passengers on the Sabena passenger flight watched, Ms Adamu struggled, then fell into a coma. She was taken to hospital where she died hours later of a brain haemorrhage.

Demonstrators entered the Belgium parliament building

The government has ordered an investigation into the incident, which was filmed by police.

The case has provoked widespread protests against the Belgian authorities.

On Wednesday, protesters gathered outside the hospital in Brussels where the woman was treated.

At another demonstration, protesters demanded the resignation of Mr Tobback.

The Belgian Committee against Expulsions also called on Mr Tobback to step down.

Correspondents say the government wants Mr Tobback to continue as minister because of a number of important issues he would have to deal with in the coming months.

He is also said to be central for the political balance of Prime Minister Jean-Luc Dehaene's four-party coalition government.

Marriage fears

Ms Adamu had earlier strongly resisted four attempts to expel her.

She fled Nigeria last March and applied for asylum because her family was forcing her to marry a 65-year-old man, who already had three other wives.

But a statement from Mr Tobback said her application "... was rejected because it was considered unfounded".

The statement added that the procedure for expulsions had been followed and the use of pillows was allowed.