London attack: 7 arrests as death toll climbs to 5

British police have conducted raids in London and Birmingham linked to Wednesday's attack in London, arresting seven people. Lawmakers were due to return to parliament one day after the deadly assault.

Authorities also revised the death toll, saying that four people are dead - including the attacker - and that 29 people are currently being treated in hospital for their injuries. Seven of those wounded are in critical condition:

Officers searched six addresses and made seven arrests in "Birmingham, London and other parts of the country," Mark Rowley, Britain's top anti-terrorism officer told reporters on Thursday. The raid was part of an investigation into the assailant in Wednesday's deadly attack in London, he confirmed. 

Rowley added that authorities believe the attacker "acted alone" and was "inspired by international terrorism."

Police have said they know the identity of the attacker but have not yet named him as investigations into his "motivation and associates" are ongoing. The senior counter-terrorism officer added that police have "no specific information about further threats to the public."

Rowley also revised the death toll, saying that four people are dead - including the attacker - and that 29 people are currently being treated in hospital for their injuries. Seven of those wounded are in critical condition.

A knife-wielding man first plowed a car into a crowd of pedestrian-son London's Westminster Bridge and stabbed a policeman outside the British Parliament on Wednesday.

Parliament is due to convene later in what Prime Minister Theresa May said was a signal that the attack would not disrupt British democracy or normal daily life.

Several Londoners appeared to echo the prime minister's sentiment to defiantly carry on with their lives. The Tower Hill Underground station, known for writing a quote of the day for busy travellers to ponder as they rush through the city, posted a picture of today's quote on Twitter: "The flower that blooms in adversity is the rarest and most beautiful of them all."

They added the hashtags "London is open" and "we are not afraid."