One person was missing after a building belonging to the church collapsed in a central Madrid explosion, Telemadrid broadcaster said on Wednesday.

Videos and images of the blast went viral on social media, show smoke coming out from a building and rubble scattered in a central street of Madrid.

A reporter for TVE public broadcaster said several had been injured, without giving details. A witness told Telemadrid broadcaster that there was at least one person trapped inside.

The building said to house an OAP home in Madrid has been destroyed by an explosion. Spanish public broadcaster TVE said the explosion took place in a building near a nursing home.

The collapsed building was a religious complex that provided residential training for priests and gave meals for the homeless.

La Sexta TV quoted government sources saying it may have been a gas leak. Officials could not immediately confirm.

A police spokeswoman said the area was being evacuated but could not confirm the source of the explosion.