Two men are being questioned after the death of a father-of-three who was killed when thieves drove over him in his own car.
Mr Howard and his wife were going on holiday to Malaga
Michael Howard, 57, of Preston, Lancashire, died after being trapped beneath the wheels of his car at Liverpool John Lennon Airport on Tuesday.
It was the third carjacking at the airport within the past three months.
On Thursday Merseyside Police were granted by magistrates more time to question a 19-year-old man, from the Woolton area of Liverpool, who was arrested on Tuesday.
Another man, 20 and from Speke, was detained by officers on Wednesday.
The force said it is still trying to locate two other men in connection with the death, which they are treating as murder.
Mr Howard, who worked for Salford-based pharmaceutical company Mawdsley-Brooks, was with his wife Elaine at the airport for an early morning holiday flight to Malaga.
In a statement released through police, Mrs Howard spoke of her husband being a loving, family man.
Police are examining CCTV images showing the Howards' arrival
"This was a happy time, and we were going on a holiday that we were really looking forward to," she said.
"Michael was a much-loved husband and father and we are completely devastated by what's happened."
She added: "Someone must know who has done this and we would ask that they please come forward and speak to the police."
Fire crews tried to release Mr Howard from beneath the car, but he died at the scene.
Detectives said Mrs Howard had got out of their metallic grey Volvo estate to get a trolley when the youths struck outside the airport's entrance.
As Mr Howard noticed one youth getting into the car, he moved around to the front of the vehicle but became trapped as the offender drove it forward.
When the Volvo stalled, the offender escaped in a maroon Ford Escort driven by another person.
This was later found abandoned about a mile from the airport.
On Wednesday, Merseyside Police released enhanced CCTV images of the Howards arriving at the airport, and are examining footage of the actual incident.
Detectives described the murder as a "despicable and cowardly crime".
Robin Tudor, corporate affairs manager at the airport, said: "It is very difficult to prevent something like this.
"But we are very vigilant."