North Wales Police said the four had gone missing from the area around Harlech and Porthmadog in Gwynedd.

Officers said the group was last seen on Sunday morning.

It is believed the boys - Jevon Hirst, Harvey Owen, Wilf Henderson and Hugo Morris - were on a camping trip in Eryri, also known as Snowdonia.

The A level students were travelling in a silver Ford Fiesta. The car's registration plate is HY14GVO.

North Wales Police said: "Officers searching for four missing teenagers in the Porthmadog area have located the vehicle they were travelling in.

"Police officers and colleagues from other emergency services are currently at the location and the families of those involved have been kept updated."

The Welsh Ambulance Service said it was called at around 10.08am to "reports of an incident" near the A4085 between Nantmor and Tan-Lan.

A road closure has been put in place near the village of Garreg.

Local councillor, June Jones, who represents the ward of Glaslyn on Gwynedd Council, told Sky News the area was "in complete shock".

"The valley's in shock, the county's in shock and everybody's feelings are very much with the families at this time," she added.

"It has been extremely wet and the rivers have been extremely high over the last few days. Obviously, it is November, the weather is bad."

The mother of one of the boys said she is "frantic with worry".

Harvey Owen's mother told Sky News she is completely "devastated" and that all she wants is for everyone to come together to help find them.

All four of the boys were studying A Levels with Shrewsbury Colleges Group.

A spokesperson said the college's thoughts were with the family and friends of the missing teenagers.

"We can confirm that all four of the teenagers are students at Shrewsbury Colleges Group and are studying A-levels with the college," they added.

"This is a very worrying time, and we all want them to be found safe and well."

Liz Saville Roberts, the MP for Dwyfor Meirionnydd, said the boys' disappearance was "very worrying".

She said the four had gone missing while on a "camping trip in Eryri".

"My immediate thoughts are with their family and friends who will be extremely concerned about their welfare," she added.

"I understand North Wales Police, local mountain rescue teams and other members of the emergency services are continuing their search efforts this morning."

Ogwen Valley Mountain Rescue earlier confirmed they had been searching local car parks.

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Locals reported a helicopter had been searching the Penrhyndeudraeth area before heading toward Nantmor and Beddgelert.

Anyone who may have seen the four are urged to contact North Wales Police.