Tampa, FL -- With so many incidents in such a short period of time this past weekend, and no word yet on whether they're coordinated, law enforcement agencies around the country are asking people to be alert.
Pipe bombs, pressure cookers, and knife attacks.
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“You're constantly always scanning,” said Officer Gig Brown, giving us a tour of so-called soft targets. Explaining what people need to be looking for.
Law enforcement agencies say it's important as ever to report anything suspicious.
“You want to look for things that stand out. Bags unattended,” said Brown pointing to three unattended backpacks in Gaslight Park right across from the Tampa Police Department.
Officer Brown showed us why even a simple walk in the park isn't so simple.
Unattended bags and garbage bins everywhere.
“What would seem to be a harmless trash can can hide an explosive device,” said Brown pointing at the lid.
There were even electronic devices that you might otherwise not even notice.
“Take something like an electric socket like that,” said Brown, pointing to a phone charging unattended. “Someone could've tampered with that.”
Extra vigilance is also recommended at soft target areas. Airports, train stations, and bus depots.
Officer Brown says people should always be looking for unusual behavior like nervousness, or even at what people are wearing. A parka in 90 degree weather, he said, should raise a red flag.
“A large garment like that can conceal and hide a lot of things. Not necessarily explosives, but weapons as well,” said Officer Brown.
Mall security, also likely tighter after a knife attack at a shopping center in Minnesota that left nine people hurt.
It’s important, says Officer Brown, to know how to get out – fast.
“It's not too much when you go into a place to plan a route to get out. Because nowadays you must be ready,” he said.
Deanna Mendez, walking to lunch, says she always tries to be vigilant.
“You never know what's behind you, what's in front of you, and watch next to you. And you have to be aware of your surroundings,” said Mendez.
But some question if a nervous public may overreact.
“Are we going to flood them with 911 calls that in the end might not amount to anything?” asked Len Gomberg.
The short answer? Cops say make the call.
“It may be nothing,” said Brown, “But we’d rather check it out and have it be nothing than to miss something and something catastrophic happens.”