MAIDUGURI, Nigeria 

Nigerians expressed worry Tuesday over security alerts recently issued by the US and British embassies warning of a heightened risk of terrorist attacks, especially in the capital Abuja.

Nureni Amodu, an Abuja-based journalist, told Anadolu Agency that most residents are in a panic.

"I avoid traffic like most residents now. It is really frightening. There is panic now in Abuja," he said.

Additional security personnel have been assigned to guard offices of political parties in the capital, said a security source.

Some elementary and secondary private schools have also shut down operations in fear, despite assurances by the authorities, the former head of the National Association of Proprietors of Private Schools disclosed.

The police said in a statement that they have activated a counter-terrorism special operations squad for the nation's capital and will hold a counter-terrorism exercise on Tuesday and Wednesday.

"The extra security measures followed recent alerts by some foreign missions in Nigeria about possible terrorist attacks," said spokesman Olumuyiwa Adejobi.

He said the police will collaborate with other security agencies to ensure the safety of the people in the capital and other parts of the country.

He did not provide further details, however.

The US and British embassies issued the security alerts on Sunday, warning their nationals in the capital to be vigilant.

"You should avoid places where crowds gather, including political meetings, religious gatherings and places of worship, markets, shopping malls, hotels, bars, restaurants, transport hubs (including train networks) and camps for displaced people,” said the UK embassy’s advisory.

Nigeria has been struggling to end over a decade of terrorist activities in Africa's largest economy. In August 2011, the Boko Haram terrorist group carried out a huge car bomb attack on the UN’s offices in Abuja, killing dozens of people, including some staff.