London - Police arrested a man at London's Luton airport on Friday for trying to take an illegal substance onto a plane, after a security alert which closed check-in for several hours, officials said.
Police said the arrest was not thought to be related to terrorism, but it caused delays at the international airport north of the capital just as the school summer holidays began following the end of term on Friday.
"An unknown substance has been spilled in the baggage area of the airport and as a precaution, the area has been evacuated whilst investigations take place," a spokesman for Luton airport told AFP.
"It was subsequently identified as cleaning fluid by Bedfordshire Fire and Rescue Service."
He added: "Flights will be subject to delays."
Police were called to investigate a suspect package in the baggage area at about 7.30am, causing about 40 staff to be evacuated, and check-in was closed 45 minutes later.
Later, the spokesman said check-in re-opened at about 11.45am.
A police spokeswoman had earlier said that a flight operated by Monarch Airlines had been stopped on the tarmac over fears that the spill might have contaminated other bags being loaded onto the plane.
"It is not thought to be a terrorist threat," she said.
More than nine million passengers used Luton airport last year, many of them on easyJet and Ryanair flights around Europe. - Sapa-AFP