Texas synagogue hostage taker Malik Faisal Akram's past raises questions about how he was allowed into US

Reports about the radical and criminal history of the British citizen who was shot dead in the Texas synagogue siege after taking Jewish worshippers hostage are raising questions on both sides of the Atlantic about how he got past both countries' intelligence services and gained entry into the United States.

The BBC reported that Akram entered the U.S. via John F. Kennedy Airport in New York earlier this month. British media initially reported that he entered on a tourist visa, while others have said specifically that he came in through the Visa Waiver Program. That program allows nationals of participating countries (including the U.K.) to travel to the U.S. for 90 days without a visa -- instead having to go through the Electronic System for Travel Authorization (ESTA) verification process. ESTA, a U.S.-based system, checks the applicants details and any criminal history and gives an approval or denial within minutes. Travelers (as with all U.S. non-citizens) are given a brief questioning by a Customs and Border Protection (CBP) on arrival in the United States.