Eyewitnesses on the ground reported seeing his charred body fall to Earth.
Mohamed Hassan, a police officer in the town of Balad 18 miles north of Mogadishu, said residents had found the dead body of an old man.
Somali aviation official, Ali Mohamoud, said only two people were slightly injured as 74 passengers and crew of the plane were evacuated after the plane made a safe landing. Local radio reported the plane was on fire when it landed.
It was not certain if all the passengers were accounted for.
The plane, operated by Daallo Airlines and headed to Djibouti in the Horn of Africa, was forced to land minutes after taking off from the Mogadishu airport, said Mr Mohamoud.
"I think it was a bomb," said the Serbian pilot, Vladimir Vodopivec, who was quoted by Belgrade daily Blic. "Luckily, the flight controls were not damaged so I could return and land at the airport. Something like this has never happened in my flight career. We lost pressure in the cabin. Thank god it ended well," the 64-year-old pilot said.
Awale Kullane, Somalia's deputy ambassador to the UN who was on board the flight, said on Facebook that he "heard a loud noise and couldn't see anything but smoke for a few seconds." When visibility returned they realised "quite a chunk" of the plane was missing, he wrote.
Mr Kullane, who was going to Djibouti to attend a conference for diplomats, also posted a video showing some passengers putting on oxygen masks inside the plane. The post was later removed from his Facebook page.
"We don't know a lot, but certainly it looks like a device," said John Goglia, a former member of the US National Transportation Safety and aviation safety expert.
Another passenger, Mohamed Ali, told The Associated Press that he and others heard a bang before flames opened a gaping hole in the plane's side.
"I don't know if it was a bomb or an electric shock, but we heard a bang inside the plane," he said, adding he could not confirm reports a passenger had fallen from the plane.
Somalia faces an insurgency perpetrated by the Somali Islamic extremist group al-Shabaab, which is responsible for many deadly attacks across the nation.