US President Joe Biden and First Lady Jill Biden visited the school in Texas where 21 people, including 19 children, were killed in a shooting.

The Bidens paid respects to the deceased at the memorial site at Robb Elementary School and attended a church mass.

People outside the church urged Biden to "do something". "We will," replied President Biden.

Authorities said an 18-year-old gunman, Salvador Ramos, used an assault-style weapon to open fire on two connected classrooms at Robb Elementary on Tuesday

killing twenty-one individuals, including 19 third- and fourth-graders. A total of 17 people were injured as a result of the shooting.

Jill Biden was spotted at the scene touching images of the children, which were surrounded by flowers and white crosses in memory of each of the deaths.