Bahrain's Public Security chief Major-General Tareq Al Hassan last night vowed zero tolerance of vandalism and said law enforcement is the ultimate solution to the problem.

He confirmed violence in a number of villages earlier yesterday and said all those arrested were referred to the Public Prosecution.

He reminded people that freedom of expression is protected under the law but it should be practised in a peaceful and civilised manner.

Several people were arrested as street violence escalated when protesters tried to march to the former GCC (Pearl) roundabout.

There was tight security across the country in anticipation of protesters turning violent on the first anniversary of last year's unrest.

Police forces were stationed in major trouble spots as the Al Farooq Junction went into lockdown for nearly two hours from 3pm. Witnesses reported large numbers of armoured vehicles stationed at the junction and several villages.

Authorities said six women were arrested when they caused havoc in the Central Market and scared shoppers away as they ran towards the barbed wire fence set up around the former roundabout at 10am.

They reportedly parked their cars nearby and made their way towards the heavily guarded zone as they shouted anti-government slogans, said witnesses.

'They parked their vehicles in the Marina Mall parking lot and posed as shoppers until they suddenly made a run for the area,' a stall owner at the Central Fish Market told the Gulf Daily News, our sister newspaper. 'They were quickly chased away and they ran towards Ramez after which they again tried to come back.'

Meanwhile, three men were also detained after they attempted to smuggle weapons into Bahrain's biggest hospital. They arrived at Salmaniya Medical Complex (SMC) at 7am and tried to go inside the hospital but were stopped by security guards, who searched their car and found weapons, including swords, a dagger and several iron rods.

'They were prevented from doing so (entering the hospital) because it was not visiting time,' said a Health Ministry official. 'The three men tried to argue with security men after which their car was searched.'

An SMC doctor revealed the hospital had beefed up its security in the lead up to yesterday's calls for increased street violence.

The doctor confirmed that the Accident and Emergency department did not receive any casualties in connection with the protests. Extra security was evident as more policemen and security personnel were stationed in and around the complex.

Trouble resumed in the afternoon when groups of men, women and children started to drive towards the former roundabout, forcing police intervention. Several of them abandoned their cars on Shaikh Khalifa bin Salman Highway and attempted to walk to the secured area.

However, they were pushed back by police who used tear gas to disperse the gathering crowds.

Protests then quickly spread across villages when masked rioters went on a rampage as they set fire to tyres and clashed with riot police in Khamis, Tashan, Sehla, Sanabis, Jidhafs, Jid Ali, Sitra, Samaheej, Bilad Al Qadeem, Nuwaidrat and Daih.

Rioters also attacked a school bus travelling from Hamad Town to Buri, resulting in a casualty. It is unknown how many students, all of whom from Buri Elementary School for Girls, were on the bus.

The masked youths reportedly surrounded the bus and terrorised the school girls before police intervened and clashes erupted, said sources.

A tear gas canister then fell onto the vehicle where an adult female passenger allegedly received the full brunt of the gas and was taken to BDF Hospital for treatment. It is not clear who threw the tear gas canister, added the sources.

The Interior Ministry confirmed the attack. However, it did reveal a brutal attack on firemen as they tried to put out a fire in Miqsha, on Budaiya Highway.

'Thugs set fire to an electric transmitter in Miqsha and attacked civil defence to prevent firemen from putting out the fire,' said the ministry on its official Twitter account.

Police also arrested several rioters after they attempted to block roads and cause panic.

Six American activists were deported last night after being detained as they accompanied opposition activist Nabeel Rajab on a march to the former roundabout. They reportedly work for Witness Bahrain.

The General Directorate of Immigration said they were deported for having applied for tourists visas under false pretenses and then taking part in illegal demonstrations.

Police also reportedly detained Mr Rajab at the Hoora police station. It comes three days after two American human rights activists were deported for attending an illegally rally towards the old roundabout. - TradeArabia News Service