The head teacher at the threatened Montgomery High School said he understands why parents kept their children away today - but said he wants them back in class tomorrow.
Tony Nicholson spoke as the day an anonymous threat-maker said he would 'kill as many people as possible' passed without incident.
Eight in 10 of the school's pupils stayed at home as police officers stood guard at the school and continued to hunt the person behind the Facebook messages, who vowed to leave a trail of 'bullets, bodies, and blood'.
The threat is being treated as a hoax, although some parents said their children will stay away until an arrest is made.
Mr Nicholson said: "Quite a few parents kept their children off and I understand why they are anxious; I'm a parent myself.
"Clearly we want more people in tomorrow, that's our number one message."
A spokesman for Lancashire Police said officers will remain at the school, in All Hallows Road, Bispham, as their investigation continues.
He said: "We will continue to provide a reassurance presence in and around Montgomery High School and are in the process of pursuing a number of strong lines of enquiry."
For all the latest, see tomorrow's The Gazette.
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