Fellow passengers said the software tycoon looked depressed and dishevelled as he entered the US on a flight to Miami after weeks on the run

John McAfee, the fugitive software tycoon wanted for questioning in Belize over the murder of his American neighbour, arrived in Miami on Wednesday night.

Fellow passengers aboard his flight from Guatemala City, where the eccentric 67-year-old was released this morning after a week of detainment, said they were prevented from disembarking while he was taken away.

Airport spokesman Greg Chin said that federal agents greeted McAfee at the door of the plane and helped him through immigration and customs formalities.

A short time later, a posting on McAfee's website announced that he was at a hotel in Miami's upscale South Beach neighborhood.

Investigators in Belize want to talk to McAfee as "a person of interest" in the murder of Florida builder Gregory Faull, his neighbour on the island of Ambergris Caye, last month. Faull, who had quarrelled with McAfee over his "vicious dogs" was found shot in the head, although McAfee has strongly denied any involvement in blog posts during a month on the run.

Guatemalan authorities arrested him and his 20-year-old girlfriend Samantha Vanegas at a hotel in the capital city last week and he spent a week in a detention center before a judge ruled he was in the country illegally and ordered his immediate deportation.

In an interview with reporters in Guatemala earlier Wednesday he said that travelling to Miami was his only option. "I can't take a flight that stops in any other country and there are only two flights going to America today. I'm happy to be going home," he said.

"I've been running through jungles and rivers and oceans and I think I need to rest for a while. And I've been in jail for seven days."

McAfee flew alone, having tweeted earlier that he and Vanegas had been "forcibly separated". He said he hoped that she would join him in the US later.

Fellow passengers said McAfee looked tired and dishevelled at the end of the flight. Matt Meehan, of Blackpool, said that passengers were told to stay in their seats "for a security check" after the plane reached the gate in Miami, then a flight attendant called McAfee's name and asked him to join security officers at the front.

"He looked like he was expecting it," Meehan said. "He looked resigned. He was sat towards the back of the plane and he walked slowly down the aisle."

Roberto Vincent, from Guatemala City, said he thought McAfee, dressed in a dark suit and carrying a black backpack, looked "depressed". "He looked just like a guy who'd been in jail for a week, he looked very tired like he hadn't slept in days," he said.

During his detention in Guatemala, which included a day in a police hospital for stress and hypertension, McAfee had access to a computer and spoke frequently to reporters. He said he believed he had become "an embarrassment" to authorities in the country, who were trying to end years of hostile relations with Belize, and apologised to the president Otto Perez Molina for his presence in the country.

The United States has an extradition treaty with Belize and it is likely that authorities will seek his return for questioning. "I don't want to be unkind to the gentleman, but I believe he is extremely paranoid. I would go so far as to say bonkers," the Belize prime minister, Dean Barrow, said after McAfee fled the country for Guatemala. "He ought to man up and respect our laws and go in and talk to the police."

McAfee, who founded and later sold the internet anti-virus company that shares his name, insists he left Belize because he would not pay $2m in bribes, a claim the authorities deny, and said he would be killed if he ever returned to the country to which he had retired.

"I simply would like to live comfortably day by day, fish, swim, enjoy my declining years," he told said when asked what he would do if he was sent back to the US.