London police announced Monday they were releasing the 12 people they arrested following the attack in the city Saturday night that killed seven and injured dozens.

Police did not say why they were releasing the individuals or what they had been suspected of doing.

The people ranged in age from 19 to 60 and were all arrested at two addresses in eastern London. Of those arrested, 10 were detained at one address in the Barking neighborhood of London.

Police released the names of two of the three attackers, Kuruam Shazad Butt and Rachid Redouane, who were shot and killed after driving a van into a crowd of people on London Bridge on Saturday night. The attackers ran out of the van following the crash and stabbed multiple people in the area and a nearby area full of restaurants and pubs.

It was the third terrorist attack in England so far this year and the second in London in just three months. The Islamic State has claimed responsibility for the attack.