MIAMI (AP) _ A postal carrier was released Friday after she was held hostage for more than four hours by a gunman who forced her to lead police on a 90-minute slow-speed chase.

The truck had been stopped in an intersection and surrounded by heavily armed police officers for more than two hours when she climbed out of the truck. The gunman remained inside.

The postal worker appeared unharmed.

``He voluntarily agreed to comply with police requests to let the hostage go,'' police Sgt. Dennis Morales said.

Police had used spikes to blow out the truck's tires, forcing it to stop in a busy intersections. The mail carrier was then moved to the back of the truck and the suspect partially blocked the passenger window with mail. Police later maneuvered a remote-controlled robot near the front of the truck to give the gunman a phone.

Miami-Dade County police Detective Randy Rossman said officers received a call around 11:15 a.m. from a woman in her passenger car who said two men were following her in another vehicle.

When officers arrived, the gunman broke into the postal truck and fled, missing as he fired shots at pursuing officers, Rossman said. The second man was arrested and was being questioned. Police said the gunman was armed with a rifle and a handgun.

A WFOR-TV reporter said that when the truck passed near her, she saw a man wearing a hat holding a gun near the female mail carrier, who was driving.

Forty-eight schools in the Miami-Dade area were locked down as a precaution, although some were released after the truck was stopped.

Manny Gonzalez, a postal inspector, told WFOR-TV that carriers receive training on how to deal with hostage situations.

Dozens of police cars and at least one police helicopter chased the truck as it wound through both main and side streets. The chase began around 11:30 a.m.

During the chase, the truck stopped for red lights and drove near the speed limit. Periodically the truck would stop and those inside would speak to bystanders before taking off again. The bystanders were then questioned by pursuing officers. One bystander ran back to the officers as if delivering the message.

The Rev. Marc Cooper gave his cell phone to the man when the postal truck stopped briefly during the chase, hoping that police could communicate with the man.

``I knew that if there was no communication back and forth between the police and the suspect that this could go on all day and all night,'' he told WSVN-TV.

Cooper said the man ``didn't seem agitated, he didn't seem nervous.''

He said his secretary called police to let them know the man had his phone. She also tried calling the man to ``pray with him,'' but she only received the phone's voice mail.

Ricardo Moreno, 37, said that when the truck passed him, the gunman seemed to be crouching between the truck's two seats, giving the driver instructions.

Police had been stopping traffic to allow the truck to drive unhindered on the streets as a safety precaution.