Los Angeles public schools will reopen today following an online threat. School Board President Steve Zimmer said officials had inspected all the schools and found no sign of any danger.

"We believe that our schools are safe. And we can reopen schools in the Los Angeles Unified School District tomorrow morning."

Officials had shut down the schools Tuesday, leaving some 643,000 students and their parents confused and frustrated. City leaders were criticized for the unprecedented move, but Los Angeles Mayor Eric Garcetti insisted the closure was the right thing to do.

"The F.B.I. has determined this is not a credible threat, something we couldn't have announced earlier in the day and I want to be very careful because that does not mean that it's conclusively one thing or another yet," he told reporters at a briefing Tuesday night.

The emailed threat to the schools came two weeks after a married couple killed 14 people and wounded 22 others at a county office building 60 miles away in San Bernardino.