Pittsburgh Mayor Ed Gaine makes a statement after 15 people were killed in a shooting at a school in Texas

(AP / KDKA) – An 18-year-old gunman opened fire Tuesday at a Texas elementary school, killing 14 children, one teacher and injuring others, Governor Greg Abbott said, and the gunman was dead.

It was the deadliest shooting at a U.S. elementary school since the shocking attack in Sandy Hook, Connecticut, nearly a decade ago.

On Tuesday, Pittsburgh Mayor Ed Ganey made a statement saying:

“Our hearts are saddened by the families, friends and classmates affected by today’s mass shooting at Robb Elementary School in Uwald, Texas. Our training centers should be safe places for all, but the sanctity of our schools is still being violated.” Too many families in our country are suffering from unimaginable and unnecessary grief.These victims – innocent children – have earned a full rich life and they deserve more than our thoughts and our prayers.If we ever recover from the trauma of gun violence in our country, we must take immediate action now to adopt genuine weapons legislation. “

An armed man entered Rob Elementary School in Uwalde with a handgun and possibly a rifle, Abbott said. Officials did not disclose the motive for the shooting, but said the shooter was a resident of a community located about 85 miles (135 kilometers) west of San Antonio.

Abbott said the shooter was probably killed by officers in charge, but events are still under investigation. Uwalde Independent School District Police Chief Pete Aredonda told a news conference that the gunman acted alone.

“He shot, horribly, incomprehensibly, 14 students and killed a teacher,” the governor said, adding that two officers had been shot and wounded but were expected to survive.