Blast damages luxury Adelaide unit

An explosion that damaged a luxury property in Adelaide's west wasn't a random attack, police say.

The blast was triggered at about 4.15am on Monday at the front of the double-storey unit at Henley Beach, causing some damage to windows and part of the facade.

The occupants were home but no-one was injured.

"The initial investigation suggests the incident is not random," police said in a statement.

They have not revealed details of the type of device involved.

Explosive experts were called in and patrols also doorknocked the local area.

Nearby residents were woken by the blast and contact authorities.