All schools in Los Angeles closed following 'credible terror threat': here's what we know so far

All schools in the large Los Angeles Unified School District were ordered to close on Tuesday morning due to a 'credible terror threat'.

Here's what we know so far:

• Around 7am (3pm GMT) local time an alert was raised that saw approximately 1,000 schools in and around the LA area closed while searches were carried out

• Approximately 650,000 students attend school in and around the city, which is the second largest school district in the US

• The nature of the threat is unknown but a schools district spokesperson said it was sent electronically and "credible"

• Officials in New York said they received a similar threat but deemed it was a hoax

• California is on heightened alert following the deaths of 14 people in San Bernardino, 60 miles east of LA, in a shooting carried out by a couple thought to have been inspired by Isis