John McAfee, the founder of anti-virus software which bears his name, has been refused asylum in Guatemala.
He is wanted for questioning in neighbouring Belize in connection with the death of his neighbour, Florida businessman Gregory Faull, last month.
Mr McAfee was arrested on Wednesday for entering Guatemala illegally and is now expected to be deported to Belize.
Guatemala's president said his country had the right to grant or deny asylum as it saw fit.
President Otto Perez Molina told a news conference that no explanation was needed as Guatemala was simply complying with the law.
"If he comes from Belize after the murder of his neighbour, it doesn't give us the impression that there's any kind of political persecution but that there is a fear of the ongoing investigation," the president said.
"So we're not going to allow people who are trying to flee an investigation to come here to Guatemala."
Mr McAfee, who maintains his innocence, was taken to hospital in Guatemala City complaining of chest pains.
He was later released from hospital and taken away in a police car. His lawyer, Telesforo Guerra, said his client had been found to be suffering from stress and an over-rapid heartbeat.
Mr McAfee says he fled Belize because he was being "harassed" by police, saying earlier this week that the country "does not have a good track record of providing safety when they ask to question you".
There is no international warrant for his arrest.
Mr McAfee posted a plea to the Guatemalan leader on his blog: "Please email the President of Guatemala and beg him to allow the court system to proceed, to determine my status in Guatemala, and please support the political asylum that I am asking for."
Mr Guerra told local radio: "We are going to go to the human rights prosecutor to lodge a complaint and file an injunction against the foreign minister for detaining him without studying his asylum request."
Bubble gum disguise
Belize officials say McAfee is a "person of interest" in the murder of Mr Faull on 11 November.
He was arrested on Wednesday at a hotel in an affluent area of the capital, Guatemala City, having managed to cross the Belize border the day before.
The 67-year-old revealed that in order to go unnoticed, he changed his appearance by dying his hair and beard, sticking chewed bubble gum to his upper gums to fatten his face and staining his teeth.
Gregory Faull's Belize home sits next to Mr McAfee's compound on a tropical island. He was found dead with a single gunshot to the head.
Mr McAfee is known to have had a long-running row with Mr Faull over the guard dogs protecting the software maker's compound.
He denies any involvement in the businessman's death and says he went into hiding so he could stay close to his Belize home and conduct his own investigation into Mr Faull's death, adding that he had little faith that the island's police would find the murderer.
In an interview with US TV station NBC, Mr McAfee offered a reward of $25,000 (£15,700) for the capture of the "person or persons" behind the killing.
McAfee has led an eccentric life since he sold his stake in the anti-virus software company that bears his name in the early 1990s.
He moved to Belize about three years ago seeking lower taxes and has lived in semi-seclusion on a heavily guarded compound until recently.