Brett and Naghmeh King are being detained for up to 72 hours while a court in Madrid decides whether they should be extradited.
Family Of SIx Escape Gas Explosion
A family has escaped after a gas explosion at their home in Gosport
Fire crews were called to Goodwood Road in the Elson area of Gosport on Monday evening after a blast involving a gas boiler.
The six members of the family, aged between 15 and 45, were treated for shock but were not injured.
The explosion caused signficant damage to the house, including blowing out doors and windows, as well as cracking walls.
Station Manager Paul Coates said: "The explosion was a significant risk to life and the occupiers are very lucky to have escaped.
"The roof was lifted by the force of the explosion and left the walls with cracks in them."
The gas board was called to check for damage to the gas main in the road.
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