Nineteen students and two adults killed in Texas elementary school shooting

• Joe Biden calls for action to stand up to gun lobby after worst school shooting since Sandy Hook
• The gunman, identified by Governor Greg Abbott as an 18-year-old man, died at the scene, reportedly killed by the police

A teenage gunman has killed at least 19 children and two adults after storming into an elementary school in Texas, officials have said, the latest bout of gun-fueled mass killings in the United States and the nation's worst school shooting since Sandy Hook a decade ago.

The carnage began when the 18-year-old suspect, identified as Salvador Ramos, shot his own grandmother, who is in a critical condition, authorities said.