The Adelaide Airport had a brief security concern this morning when a man suddenly broke in with his car crashing into the tarmac. The man suspected of drunk-driving or mentally ill has been subdued by the airport police moments after the said incident.

Some flights were delayed, but flight schedules of those arriving by noon are on time.

Rebecca Stokes, a senior constable in the South Australia state police force, said in a phone interview today from Adelaide that all has been handled fairly well by the Australian Federal Police at the airport.

"Tthey've got it all under control," Stokes said by phone today from Adelaide.

She noted that the man, who was either "intoxicated or with a mental illness," has already been put under police custody.

She denied that it was an act of terrorism related to the visit of Prime Minister Julia Gillard to Brisbane today.

There has been one arrest and "mental health or intoxication," not terrorism, is the probable cause, she said.

Australia's major airports is handled by the federal police force as part of the nation's counter-terrorism measures. Prime Minister Julia Gillard was scheduled to be in Brisbane in Queensland state at the time of the security breach at Adelaide airport.

According to a related Bloomberg report, the Australian government said it has proposed to lift spending by A$200 million ($197 million) over four years to strengthen Australian domestic and international aviation security.