Crisis negotiators have secured the release of a ninth hostage from the hijacked plane at Stansted airport.

Police said the hijackers released an asthmatic Afghan man aged 40-45, after he complained of breathing difficulties.

The man, who told police he was a trader, has been treated and is being questioned by security services to gain more information about conditions in the plane.

Assistant Chief Constable John Broughton told a news conference that the only formal requests police had received from the hijackers were "house-keeping" ones - meaning requests for food, water and other supplies.

'No change'

He added: "The negotiations are going forward in a professional way, in a fairly calm way, so no real change from where we were before."

Police experts have warned that negotiations to free more than 150 hostages could last several days.

As the crisis entered a third day, the negotiators told the hijackers they wanted a peaceful end to the stand-off.

Eight hostages were freed on Monday by a hijackers believed to be armed with grenades and pistols.

Security forces have surrounded the plane, at Stansted, near London. But Joe Edwards, Assistant Chief Constable of Essex, said negotiation remained the favoured option.

He added: "It can be a very protracted technique. It could go on for days."

Five hostages - one woman, two children and two men - left the aircraft shortly after midday on Monday.

Four of the five, a man of 26, a woman of 17 and two children, were from the same family, said police.

The five - thought to be Afghan - were interviewed by police.

Mr Edwards said three other passengers released three hours later were a 36-year-old woman, her 47-year-old husband and an unrelated woman of 30.

The hostages indicated they had been treated well on board.

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The choice of who to let go had been made by the hijackers, he said, adding: "The mood on board is calm."

Stomach ailments

Supplies of food, drink and medicines have been delivered several times to those on board since the jet landed in the UK at 0200 GMT on Monday.

Early on Tuesday, breakfasts of omelettes and mushrooms, together with a second power generator, were delivered on board.

Police say some of the medication has included treatments for "minor tummy ailments".

Officers did not give details of the terms of the releases, or of any demands made by the hijackers, other than for food, water and other supplies.

Mr Broughton said: "We have been seeking all the time to improve sanitation and conditions on board.

"They've been on the aircraft for some considerable time and we're conscious that we want to improve conditions and ultimately bring this to a successful conclusion."

Issues discussed

He said the hijackers had made no specific demands.

A police spokeswoman said "issues" were being talked about with the hijackers, but that was different from demands being made.

SAS soldiers are believed to be part of the standby operation at the airport.

For much of Monday, airport chiefs operated only a skeleton service, but on Tuesday 99% of scheduled flights were operating.

Stansted, which has seen several similar incidents in the past, has well-rehearsed procedures for dealing with hijacks.

The Boeing 727 was hijacked on Sunday during an internal Afghan flight.

It landed twice in Central Asia, where at least 10 passengers were released and the plane refuelled.

Several hours later, it stopped in Moscow, where another 10 passengers were freed.

The hijackers' motives are unclear, but one report, from Pakistan, said the group wanted the release of a political prisoner.

In Afghanistan, the ruling Taleban movement said that while British authorities were free to negotiate with the hijackers, the Taleban itself would not give in to their demands.

Akhtar Mohammad Mansoor, the Taleban's minister for civil aviation and tourism, said the UK authorities should end the hijack by storming the plane.

Also:

Analysis: Hijack - the last resort
Stansted travel chaos eases
Who are the hijackers?
Negotiating with hijackers
Stansted's hijack history

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