Cartagena, Colombia (CNN) -- Police dressed in black burst through a door, opening fire and rushing toward a man crouched in the corner.
"We are the National Police," one officer says. "Stay calm."
The men in black are members of an elite anti-terrorism unit of Colombia's National Police.
And the recent hostage rescue simulation -- which used live ammunition and high-tech weapons -- was part of more than a year of training to prepare for the Summit of the Americas, which will draw 33 heads of state and government from across the Western Hemisphere to Cartagena, Colombia, this weekend.
More than 7,600 police officers and thousands more troops are set to be deployed in the walled colonial city as part of stepped up security for the summit, which started Monday with a youth conference.
Submarines are patrolling in the coastal waters near the city, officials said.
From the air, armed helicopters will be hovering at the ready.
On land, snipers in strategic locations throughout the city will be watching for suspicious activity 24 hours a day during the summit.
Anti-explosive robots and radiation detectors are also part of the stepped-up security detail.
"We have equipment to neutralize any type of threat," National Police Maj. Giovani Riano said.
From a hidden command post, police will monitor images of the city, using images from 500 cameras, officials said.
Intelligence agencies from 27 countries are sharing information as part of the security operation, said Gen. Jose Leon Riano, deputy director of the National Police.
Journalist Fernando Ramos and CNN's Patricia Janiot contributed to this report.