Armed police have raided a home and closed off several roads in Birmingham for more than two hours.
Police officers were seen standing outside a property in Hagley Road, which was cordoned off by police, news reports say. Five Ways Island and several other routes near the home were also blocked off.
Dozens of officers, some armed with weapons were seen heading towards an residential property near to the Bearwood part of the city.
Sky News said that West Midlands Police have referred enquiries over the raid to the Metropolitan Police saying that it was "not prepared to discuss the matter for operational reasons."
In a short statement, West Midlands Police said: "There is an ongoing police operation, no further details are being given at this stage."
The broadcaster said it was not immediately clear if the raid was in any way connected to the terror attack in Westminster, London on Wednesday.
However, BBC reported that the vehicle used in the Westminster attack could have been rented from an address in Birmingham. This could not be immediately confirmed.
Four people, including police officer Keith Palmer were killed by a lone terrorist while around 40 others were injured in the incident in Westminster on Wednesday (22 March). The attacker was later shot dead by an armed police officer.