Heidi Montag and Spencer Pratt arrived back at Los Angeles airport after apparently eloping in a 'secret' wedding ceremony in Cabo San Lucas, Mexico yesterday.

But as the pair walked hand-in-hand to their limousine, it appeared that they hadn't exchanged wedding rings, fueling rumours that their marriage was a money-spinning publicity stunt.

Their secret elopement over the weekend - where MTV cameras happened to be on-hand for the nuptials -  may not be legally recognised in the United States.

Talking about their ceremony, Spencer told the press "We’ve never been happier.”

He added, “Like other elopements that happen outside the country, we’ll take care of the legal details when we get home.”

The Hills stars got engaged in 2007.

See Speidi looking tanned from their getaway below