Suddenly, police with guns drawn kicked in the door and stormed in, shooting to death the couple's two dogs and seizing the unopened package.
In it were 32 pounds of marijuana. But the drugs evidently didn't belong to the couple.
Police say the couple appeared to be innocent victims of a scheme by two men to smuggle millions of dollars worth of marijuana by having it delivered to about a half-dozen unsuspecting recipients.
The two men under arrest include a FedEx deliveryman; investigators said the deliveryman would drop off a package outside a home, and the other man would come by a short time later and pick it up.
Now, federal authorities say they're looking into how local law enforcement handled the July 29 raid. FBI Agent Rich Wolf said late Thursday that the bureau had opened a civil rights investigation into the case.
A furious Calvo said earlier Thursday that he and his wife, Trinity Tomsic, had asked the government to investigate.
"Trinity was an innocent victim and random victim," Calvo told reporters outside his two-story, red-brick house in this middle-class Washington suburb of about 3,000 people. "We were harmed by the very people who took an oath to protect us."
"It was a horrible, horrible incident," Calvo told Early Show co-anchor Harry Smith Friday, "but I think it's also the kind of thing that happens, and I don't think we would have realized that until it happened to us."
"What's really troubling," Calvo continued, "is they didn't have a proper warrant to do what they did. They actually didn't give us a warrant at all until 71 hours after it happened. And that's really what's disturbing -- despite all the mistakes that were made, they're holding to their guns, saying they did nothing wrong.
"This happened to us. We can't get our dogs back, and we know that. But the reason we asked for federal authorities to investigate this is because this is a systemic problem, and we want to make sure that, while it happened to us and that's a tragedy, we don't want it to happen to anyone else."
Calvo insisted the couple's two black Labradors were gentle creatures and said police apparently killed them "for sport," gunning down one of them as it was running away.
"Our dogs were our children," said the 37-year-old Calvo. "They were the reason we bought this house because it had a big yard for them to run in."
The mayor, who was changing his clothes when police burst in, also complained that he was handcuffed in his boxer shorts for about two hours along with his mother-in-law, and said the officers didn't believe him when he told them he was the mayor. No charges were brought against Calvo or his wife, who came home in the middle of the raid.
Prince George's County Police Chief Melvin High said Wednesday that Calvo and his family were "most likely ... innocent victims," but he would not rule out their involvement, and he defended the way the raid was conducted. He and other officials did not apologize for killing the dogs, saying the officers felt threatened.
The FBI will monitor how effective, fair and professional the law enforcement agency's conduct was during the incident, Wolf said. A police spokesman declined comment Thursday on the FBI investigation.
Police announced Wednesday they had arrested two men suspected in a plot to smuggle 417 pounds of marijuana, and seized a total of $3.6 million in pot. Investigators said the package that arrived on Calvo's porch had been sent from Los Angeles via FedEx, and they had been tracking it ever since it drew the attention of a drug-sniffing dog in Arizona.
Police intercepted it in Maryland, and an undercover detective posing as a deliveryman took it to the Calvo home.
Calvo's defenders - including the Berwyn Heights police chief, who said his department should have been alerted ahead of time - said police had no right to enter the home without knocking.
But officials insisted they acted within the law, saying the operation was compromised when Calvo's mother-in-law saw officers approaching the house and screamed. That could have given someone time to grab a gun or destroy evidence, authorities said.
Neighbors in Berwyn Heights, which Calvo described as "Mayberry inside the Capital Beltway," have rallied around the couple. On Sunday night, supporters gathered on a ballfield to pay tribute to the family and the dogs. A banner on the wooden fence around Calvo's yard read, "Cheye and Trinity, We support you, Friends and Citizens of Berwyn Heights." Around it were dozens of handwritten messages from supporters.
In addition to being the part-time mayor, Calvo works at a nonprofit foundation that runs boarding schools. His wife is a state finance officer.
"When all of this happened I was flabbergasted," said next-door neighbor Edward Alexander. "I was completely stunned because those dogs didn't hurt anybody. They barely bark."
The case is the latest embarrassment for Prince George's County officials. A former police officer was sentenced in May to 45 years in prison for shooting two furniture deliverymen at his home last year, one of them fatally. He claimed that they attacked him. In June, a suspect jailed in the death of a police officer was found strangled in his cell.
Calvo said he was astonished that police have not only failed to apologize, but declined to clear the couple's names.
His wife spoke through tears as she described an encounter with a girl who used to see the couple walking their dogs.
"She gave me a big hug and she said, `If the police shot your dogs dead and did this to you, how can I trust them?'" Tomsic said. "I don't want people to feel like that. I just want them to be proud of our police and proud to live in Prince George's County."