American and British strikes unleashed against Afghanistan were aimed at 30 military targets, Defence Secretary Geoff Hoon said today.

The strikes were designed to "damage, disrupt and destroy" al Qaida terrorist sites in the country.

Mr Hoon said: "All 30 were military targets, three in Kabul, four close to other urban areas and 23 elsewhere.

"Neither the Afghan civilian population nor their homes or property have been targeted."

Mr Hoon paid tribute to British forces' contribution to the assault, which included Tomahawk missiles fired from two submarines, HMS Trafalgar and HMS Triumph.

Operation Enduring Freedom began with the launch of 50 Tomahawk Cruise missiles from American and UK ships and submarines at 5.27pm British time.

Bombers then moved in to strike at bin Laden's al Qaida terror machine in retaliation for the September 11 atrocities in New York and Washington.

Targets in and around the capital Kabul, Jalalabad in the north and the Taliban's spiritual home of Kandahar in the south are thought to have been blitzed at least twice.

Anti-aircraft fire heard over Kabul shortly before midnight British time was thought to mark a third round of strikes at the city.

A Taliban official claimed 20 civilians were killed in the barrage.

The Pentagon said damage assessment was still going on and it was too early to say if there were civilian casualties.

The Afghan Islamic Press claimed today that five Taliban soldiers were killed in air strikes on the Shindand air base at Herat in western Afghanistan.

An oil depot was blown up in the attack - not far from the Iranian border - but Mullah Khairullah Khairkhwa, governor of Herat province, said it was a small oil reserve. He said: "It does not matter."

As the attacks began, US president George Bush said in an address to the nation from the White House: "We are supported by the collective will of the world."

UK Prime Minister Tony Blair said: "This is a moment of utmost gravity for the world. None of the leaders involved in this action want war. None of our nations want it. We are peaceful people.

"But we know that sometimes to safeguard peace we have to fight. Britain has learnt that lesson many times in our history. We only do it if the cause is just. This cause is just."

US Defence Secretary Donald Rumsfeld said an initial goal of the strikes was to render air defences ineffective and to wipe out the military aircraft of the Taliban.

He also stressed that allied forces were already dropping humanitarian supplies to the people of Afghanistan.

Taliban claims that they had shot down a plane were dismissed by US officials, who said none of their fighters or bombers had been hit.

Afghan officials said bin Laden and Taliban leader Mullah Mohammed Omar had survived the first wave of attacks.

The deputy Taliban ambassador to Pakistan told American broadcaster NBC that the air strikes would unite Afghans behind the regime.

Mohammad Suhail Shaheen said: "We are victims of this expansionist antic by America.

"Such tactics will never achieve political goals. The former Soviet Union didn't achieve its political goals by invading Afghanistan."

In Karachi, Pakistan, Rehmatullah Kakazada, the consul-general for Afghanistan's ruling Taliban, condemned the attack and said: "We are ready for jihad (holy war)."

And in a defiant video message screened on Arabic satellite station Al-Jazeera, bin Laden said of the September 11 attacks: "America was hit by God in one of its softest spots.

"America is full of fear from its north to its south, from its west to its east. Thank God for that."

Mr Blair said of the Taliban: "They were given the choice of siding with justice or siding with terror. They chose to side with terror."

The Foreign Office said it was still trying to confirm reports that Sunday Express journalist Yvonne Ridley had been freed.

The 43-year-old reporter was arrested on September 28 near the north-eastern city of Jalalabad with two male Afghan guides while trying to report on conditions in Afghanistan.

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