Amsterdam/Washington, Dec 26 (DPA) Security measures at Amsterdam’s Schiphol Airport were stepped up Saturday morning after a Nigerian passenger allegedly tried to set off an explosive device on a Northwest Airlines flight from Amsterdam to Detroit the day before.

All passengers to the US are now being body-searched individually, a spokesperson for the National Coordinator for Counterterrorism (NCT) said.

An investigation into the “operational affairs” of the Delta Airlines plane – with the flight operated by Northwest Airlines – involved in the incident had also been launched, the spokesperson added, declining to give further details.

Passengers on the flight said they heard a bang shortly before landing. Eyewitnesses subsequently saw flames and smoke coming from one of the seats where a Nigerian man was seated.

A passenger threw himself on the Nigerian while other passengers and crew successfully put out the fire, using fire extinguishers and blankets. They subsequently dragged him to the front of the plane, away from the other passengers.

Three people, including the Nigerian, sustained injuries from the fire. One passenger was treated in the hospital.

After the plane had safely landed, the man was handed over to the US police for questioning.

Shortly after the incident, the Nigerian reportedly stated he had acted on an assignment of Al Qaeda.

Pete King, a member of the US Homeland Security Committee of the House of Representatives, said the Nigerian was found in a database of people allegedly involved in terrorism.

“I think he does have connections to Al Qaeda,” King said, “his name popped up immediately.”

US President Barack Obama was informed of the incident during his Christmas vacation in Hawaii.

The suspect is said to have boarded KLM flight 588 from the Nigerian city Lagos to Schiphol Airport.