New York, May 28 (IANS): The New York Police Department (NYPD) has revealed that threats against schools in the city have reached epidemic proportions.

The NYPD has fielded 334 threats of violence against schools since September 2017, an average of two a dayn and 18 per cent more than the 282 threats received over the same time last school year, a department official told The New York Post on Sunday.

While the NYPD did not give the number of arrests made in connection to the threats, it said the problem has worsened as school shootings continued around the country, including the February 14 massacre of 17 people at Marjory Stoneman Douglas High School in Parkland, Florida, and the May 18 killing of 10 at Santa Fe, Texas.

A week after the Texas tragedy, New York city schools reported threats on three consecutive days.

The threats have come verbally, by phone, letter, e-mail and on social media, NYPD spokeswoman Sgt. Jessica McRorie told the New York Post.

A school that President Donald Trump's son Barron once attended was evacuated earlier this month and closed after the words "shooting today at 12.45" were found written on campus.

The school reopened the following day and there is an ongoing investigation, the NYPD said.

School staffs get trained annually on safety protocol, including a requirement to report threats immediately to the NYPD, according to the city's Department of Education.

Schools must conduct four lockdown drills and eight evacuation drills each year to prepare for shootings and other emergencies.