Tight security is still in force at UK airports across the UK amid heightened fears of an attack by terrorists.
www.channelnewsasia.com First created : 15 February 2003 1043 hrs (SST) 0243 hrs (GMT) Last modified : 15 February 2003 1043 hrs (SST) 0243 hrs (GMT)
A security scare shut part of Heathrow for 90 minutes and four men were arrested nearby as airports stay on a heightened state of alert on Friday.
Heathrow Airport's Terminal Two was closed for an hour an a half after a "suspect package" - later declared safe - was found.
Two people arrested in Hounslow, near Heathrow, on Thursday have been released without charge.
Anti-terrorist police have handed four others over to the immigration authorities, after separate arrests on Thursday in Langley, Berkshire, near Heathrow.
Meanwhile a 37-year-old Venezuelan man is still being questioned by police, after being caught trying to smuggle a live grenade through customs at Gatwick.
British Airways staff are travelling to Venezuela to investigate how the man managed to board a plane without the weapon being detected.