Prime Minister Theresa May said the attacker who killed three people near the British Parliament was born in Britain. And he was investigated by the country's intelligence agency MI-5 in relation to concerns about violent extremism. May added that there was no earlier information on the suspect’s plan or his reason for carrying out the attack. Investigators believe that the attacker was influenced by “Islamist ideology. Shortly after May spoke with members of the parliament, the Islamic State terrorist group claimed responsibility saying the attacker was a "soldier of Islamic State." On Wednesday, the attacker crashed an SUV into pedestrians near the Parliament building. The large vehicle killed two persons and injured many others. The attacker then stabbed a police officer to death before being fatally shot by another officer.