American Christians should be armed when they go to church, according to Texas Attorney General following the worst mass shooting in the state's history.

Republican Ken Paxton said churches should consider 'arming some of the parishioners' or hiring security guards following the incident at First Baptist Church in Sutherland Springs, where at least 26 people were killed and many more injured.

'It's going to happen again,' he told Fox News just hours after the shooting that killed victims aged five to 72 dead.

If more churchgoers were armed 'there's always the opportunity that the gunman will be taken out before he has the opportunity to kill very many people', he said.

'We've had shootings in churches for, you know, for forever. It's going to happen again, and so we need people in churches, professional security or at least arming some of the parishioner or the congregation so they can respond if something like this – when something like this happens again.'

It comes after President Donald Trump refused to enter a debate about gun laws after the worst shooting in US history in Las Vegas a month ago left 56 dead and 546 injured.

Speaking from Tokyo on Monday Trump blamed the incident on the attacker's 'mental health problems' and said it 'isn't a guns situation.' He said it was lucky there was an armed local on the scene who shot at the attacker, otherwise 'it would have been much worse.'

But Texan Democrat senator Joaquin Castro pointed to other mass killings in local history and 'Texans have been haunted by three generations of mass murder'.

He called for Republicans to abandon their obsession against any form of gun control.

'We're gripped by this idea that the Second Amendment is absolute and also by the NRA's subtle argument that puts us into this false choice, this binary choice where if you're going to pass a gun law, it has to make sure that it prevents every gun death, and if it doesn't prevent every gun death, then we shouldn't pass any law.'

The Democrat senator for Connecticut Chris Murphy rubbished the idea anyone stopped this attack.

Former President Barack Obama prayed for wisdom to know what 'concrete steps we can take to reduce the violence and weaponry'.

Under state law in Texas, churchgoers are allowed to carry a concealed weapon in houses of worship, as long as the house of worship does not specifically forbid it. Texans are also allowed to sell a gun to another citizen without conducting any background check to confirm they are not prohibited from owning guns.