Previous discoveries have proven to be false alarms
The United States is testing materials found in Iraq that may have been used in the manufacture of chemical weapons, the Pentagon has said.
Officials say it will be several days before they have results.
They would not say when or where the materials were found, but a US television station reported that 14 unmarked drums had been found near Bayji, about 210 kilometres (130 miles) north-west of Baghdad, on Friday.
The Pentagon announcement came as hospital workers in Baghdad said at least 12 people had been killed by explosions at an ammunition dump on the edge of the Iraqi capital.
US military officials also said they had detained General Hossam Mohammed Amin, the former head of Iraq's arms monitors and the six of clubs in the US "most wanted" playing card deck.
Correspondents say it is hoped that he will be able to provide details of Saddam Hussein's weapons programmes as well as an insight into the regime's inner circle.
America's ABC News reported that US chemical weapons specialists had tested a suspected mobile weapons laboratory.
Initial tests showed the presence of a nerve agent and a blistering agent, but the Pentagon remained cautious about the find.
The materials are being sent to the US for more comprehensive testing. The tests performed in Iraq can give false positives because similar chemicals are used in pesticides.
At least two previous suspected chemical weapons discoveries have turned out to be harmless.
But the barrels found at Bayji were near missiles and gas masks, making the US more suspicious. US forces escorted an ABC news crew to the site.
In a separate discovery, the UK newspaper the Sunday Telegraph said it had found documents linking Saddam Hussein with Osama Bin Laden.
The newspaper said an envoy from Bin Laden's al-Qaeda network travelled to Baghdad at the Iraqi leader's invitation in 1998 "to establish a relationship based on their mutual hatred of America and Saudi Arabia".
The Sunday Times, meanwhile, said that France had regularly briefed Iraqi officials on its dealings with the US as recently as late 2001.
The paper said the information was contained in files found in the wreckage of the Iraqi
The briefings, which came partly from "friends of Iraq" at the French foreign ministry, kept Saddam Hussein abreast of America's war plans, according to the paper.
Meanwhile, hundreds of Iraqis staged a fresh demonstration in central Baghdad on Sunday to demand the full restoration of phone lines, water and electricity.
US forces arrested a self-proclaimed "mayor" of Baghdad, Mohamed Mohsen al-Zubaidi, for misrepresenting himself.
Mr Zubaidi claimed to have been elected by a broad-based grouping, but coalition officials repeatedly said they did not recognise him or his position.
The man due to lead an interim administration in Iraq, Jay Garner, has said all Iraqis will see their basic services restored in three weeks.
A newspaper linked Osama Bin Laden with Iraq
On Saturday, demonstrators chanted anti-US, pro-Islamic slogans, after at least 12 people died in a series of explosions at an arms dump near Baghdad.
A US officer said "hostile forces" had fired flares into the depot, but Baghdadis accused American troops of storing weapons in a residential area.
The explosions, in the Zafaranyah neighbourhood of southern Baghdad, demolished at least four houses.
In other developments:
- US Defence Secretary Donald Rumsfeld has arrived in the United Arab Emirates at the start of a tour of the Gulf region and South Asia
- American diplomatic sources at the United Nations confirm that Washington is working on proposals for a new UN resolution to address the changed situation in Iraq
- The US defence department starts sending Iraqi exiles to Baghdad to join a temporary US-led administration, the New York Times reports
- The UN refugee agency says it is planning to help up to half a million Iraqi refugees return home from exile.