Fears grow for missing 13 year-old twin brothers who BOTH vanished while swimming off Texas pier

A Texas family is hoping for a miracle after twin 13-year-old boys vanished on Sunday in chest-deep water at the beach, where they were wading despite being unable to swim.

Josue and Jefferson Perez had travelled from their Houston home for a day at the beach in Galveston.

The boys were last seen around 4:30pm on Sunday playing in the water near the Pleasure Pier, around 20 yards from the shore. 

Rip currents around the pier can be strong, officials said, and the sea temperature was a chilly 67F. 

No one in the family saw them go underwater, but after they went missing the relatives raised the alarm.

Twin brothers Josue and Jefferson Perez, 13, were last seen at around 4:30pm on Sunday near the Pleasure Pier in Galveston, wading in chest-deep water 20 yards from the shore

Police are seen assisting the search after dark on Sunday evening. The boys are yet to be found, 24 hours after they went missing

Galveston search and rescue teams scoured the area with helicopters and jet skis, but they boys are yet to be found.

'Nobody confirms seeing them go underwater,' said Lt. Austin Kirwin with Galveston Beach Patrol. 

'So essentially what happened is they were out in the water, the parents briefly lost sight of them, and they looked back up into that area, and they did not see them any longer.' 

The Galveston County Community Emergency Response Team, Beach Patrol, the U.S. Coast Guard, and volunteers have been out searching for the twins since 5.30pm on Sunday night. Divers are also assisting the teams.

Kirwin said weather conditions are hampering the search. 

'The real limiting factor for us right now is this fog rolling in,' he said at a press conference on Monday. 

Lt. Austin Kirwin, with Galveston Beach Patrol, said the waters were cold and rip currents were common in the area

Rescuers are still hoping to find the boys alive in the waters or on the shore

The Pleasure Pier in Galveston is a popular tourist site, and from March 11 there will be lifeguards on the beach

'That's going to inhibit us from being able to search as well as we want to. 

'Also, the water is still relatively cold. It's about 67F this morning, so without a wetsuit, the length of time you can be in that water is diminished.'

He noted that the waters swirling around objects jetting into the sea - such as jetties and the Pleasure Pier - were dangerous, because strong currents can create rips.

'In the event that you do get caught in a rip current, the key point is, do not panic,' he said. 

'If you just relax and try to keep your calm, the current will eventually bring you back to shore. 

'The main killer in drownings is that panic mode.'

Lifeguards will be on the beach from March 11, when the main swimming season begins.