Three small bombs have exploded in the London Underground and one on a bus in London, two weeks to-the-day after four suicide bombers killed 56 (including themselves) in the same transport systems. The attacks were minor and only caused one reported injury, however preliminary reports indicate the bombs were intended to be much more powerful and malfunctioned.

Scotland Yard has also confirmed that they investigated an ‘incident’ at University College Hospital near one of the bomb sites. The nature of that incident is currently unknown and the hospital has now returned to normal operation.

According to various news sources, a witness to one of the explosions saw a man holding a rucksack which exploded in his hand. The man made an exclamation as if something had gone wrong before rushing off the train and escaping.

U.S. transit systems remain on a high state of alert from the London attacks two weeks ago.