LONDON (AP) — The Latest on the London subway attack investigation (all times local):

5:45 p.m.

British police say a 21-year-old man arrested over last week's London subway bombing has been released without being charged.

The man, originally from Syria, was detained outside a fast-food restaurant in west London on Saturday, a day after the attack at Parsons Green station. Thirty people were injured when a homemade bomb placed inside a bucket wrapped in a supermarket bag, partly detonated during the morning rush hour.

Five other men have been arrested and remain in custody, including an 18-year-old from Iraq detained at the English Channel port of Dover on Saturday.

Three men were arrested in Newport, Wales, earlier this week and a 17-year-old was held early Thursday in south London.

None of the suspects has been charged, and their names haven't been released.

___

9:50 a.m.

British police have arrested a sixth person in connection with last week's attack on a London subway train.

Detectives arrested a 17-year-old under the Terrorism Act early Thursday in south London. A search of the property where he was found is underway.

Commander Dean Haydon, head of the Metropolitan Police Service's Counter Terrorism Command, says a "significant amount of activity" has taken place since a homemade bomb partially detonated during the morning rush hour Friday, injuring 30 people. The attack sparked a manhunt for the perpetrators and prompted the government to briefly raise the national terrorism threat to the highest level.

Detectives arrested three men earlier this week in Newport, Wales. An 18-year-old refugee from Iraq and a 21-year-old from Syria who were arrested previously remain in custody.