Two people were arrested under the Terrorism Act early Tuesday morning in Greater Manchester, central Britain.
The arrests "were targeting individuals suspected of possession of information that could be used for a terrorism purpose," the British Broadcasting Corporation (BBC) news quoted a spokesperson for the Greater Manchester Police as saying.
Some 250 unarmed officers were deployed for the anti-terrorism operation believed not to be linked to any other investigation.
Also on Tuesday, two men are due to appear in Bow Street Magistrates' Court in London in connection with an investigation into an international terrorist plot.
One man, 21, arrested last week, faces charges of conspiracy to murder and causing public nuisance with poison or explosives.
The other, 28, from London, is charged with separate offenses under the Terrorism Act.
Source: Xinhua