London police
An armed police officer patrolled outside New Scotland Yard the morning after an attack by a man driving a car and wielding a knife left three people dead and dozens injured, in London, March 23, 2017. REUTERS/Neil Hall

London police believes Wednesday’s attack near the U.K. Parliament was linked to Islamic terrorism, British Defense Minister Michael Fallon told BBC Radio Thursday. Seven people have been arrested and six addresses have been raided in London, Birmingham and elsewhere in connection with the attack, police said.

"The police are investigating this man [the attacker], his associates, where he came from," Fallon told BBC Radio. "[They are] checking urgently whether other people were involved in this. Their working assumption is that this is linked to Islamic terrorism."

The police also revised the total death toll down to four that included the attacker, a police officer guarding Parliament and two civilians. According to the law enforcement officials, the attacker — whose identity and nationality has not yet been released — acted alone and is believed to have been “inspired by international terrorism.” Police conducted the raids overnight across several locations in the country.

“We have searched six addresses and made seven arrests. The inquiries in Birmingham and other parts of the country are continuing,” Mark Rowley, Metropolitan Police’s assistant commissioner for specialist operations, said Thursday.

Rowley also said police had “no specific information about further threats to the public at this time.”

The attack left 40 people injured after the knife-wielding assailant drove an SUV over pedestrians on Westminster Bridge and rammed the vehicle into the Parliament gates. The man then jumped the fences and fatally stabbed police officer PC Keith Palmer. The attacker was shot dead by police on the Parliament grounds.

According to Rowley, the deceased civilians include a woman in her 40s and a man in his 50s. Although, officials are yet to release their identities, British media reported that the woman has been identified as 43-year-old Aysha Frade, who worked as a teacher in London. Her family reportedly hails from Betanzos, Galicia in northwest Spain.

“The rumors that started going round last night are sadly true,” Betanzos' mayor told the Guardian. “I didn’t know her but she has two sisters who run an English school here and other relatives in the area. It’s a tragedy.”