A manhunt was underway for suspect(s) linked to the bucket bomb that detonated on a packed subway train during Friday morning rush hour, injuring at least 22 people. 

Police quickly called the incident on the District Line train at Parsons Green station a "terrorist incident." It was the fifth terrorist attack in Britain this year. Police said they have not arrested anyone in connection to the bombing but hundreds of detectives were trying to hunt down the perpetrator or perpetrators.