Businesses in London's financial center, the City, are being advised by police to tighten their security, a week after the fatal explosions that killed at least 53 in the British capital.

The advice includes barriers near the entrance to buildings, more checks on visitors and underground car parks, and less entry points to ensure adequate cover by security staff, Financial Times reported Friday.

A police official said the advice is a precautionary measure, with no specific intelligence of any imminent attack on the financial center.

Chief Superintendent Alex Robertson, head of the City's anti-terrorist section, said that the need for robust security became all the more pressing after the police found out that the explosions last Thursday were carried out by suicide bombers.

The City has been targeted in the past by bombers.

Source: Xinhua