DAYTONA BEACH, Fla. — A person was taken into custody Friday morning who police say made an online threat to be Parkland copycats at Mainland High School on the anniversary of the massacre.

The arrest comes a day after firecrackers went off on campus, prompting a shooting scare and "code red" lockdown. Three students were taken into custody in connection to that incident.

"I had one headphone in. And I was like, what is that sound? I heard, pop pop," Mainland High School student Travis Hubbert Jr. said about Thursday's scare.

“I’m like, 'OK, they just popping off firecrackers.' It might be a gun, you never know. So everyone started running."

The school was put on lockdown until investigators determined there wasn't an actual weapon. Firecrackers had been set off in a stairwell.

Hours later, a threat circulated on social media. People began sharing the post, urging students not to go school Friday, just in case. It said shooters were threatening to be Parkland copycats on the two-year anniversary of the massacre at Marjory Stoneman Douglas High School.

The threat claimed the firecrackers were a test to gauge police arrival times, but in truth the firecracker incident was unrelated. 

"The days of doing this type of stuff is long gone," said Daytona Beach police Chief Craig Capri. "We live in a different world now. You go back 30 years and lit off a pack of firecrackers. nobody would even think nothing of it they'd probably laugh. Now a days not so much you're going to think its an active threat an active shooter and these kids watch the news and this is a high school so you can only imagine the trauma these 4 kids caused."

Normally packed school buses were largely empty Friday — Valentine's Day — as many Mainland parents and guardians kept students home, despite extra law enforcement officers on campus.