A Japanese journalist freed over the weekend by captors in Afghanistan managed to send two Twitter messages before his release while teaching a captor how to access the Internet on a new cell phone, he said Tuesday.

Kosuke Tsuneoka, a freelance journalist, was released from five months of captivity on Saturday. His freedom came a day after the first messages since his disappearance were posted to his Twitter account.

"i am still allive [sic], but in jail," read a message sent at 1:15 p.m. GMT on Friday. It was followed a few minutes later with a second message, also in English, that read, "here is archi in kunduz. in the jail of commander lativ." The message referred to the Dasht-e-Archi district of Kunduz where he was being held.

Tsuneoka hadn't been heard from since disappearing on April 1, so the messages gave hope to family and friends, but were also greeted with skepticism by some who questioned aspects of them.

Why were they sent in English when Tsuneoka had been using only Japanese on his Twitter account? Why were they sent through Twitter's mobile Web interface when previous messages had been sent using the Gravity Twitter cell phone client? And how was he managing to post messages if he was in prison?

On Tuesday, speaking in Tokyo, Tsuneoka answered these questions and revealed how he managed to convince his captors to give him access to the Internet.

It began three days earlier when one of his captors, whom he identified as a low-ranking soldier, was showing him a new cell phone. The phone, a Nokia N70, is advanced compared to what many are using in Afghanistan and the soldier didn't know how to use it.

"He asked me if I knew how to use it, so I had a look and explained it to him," said Tsuneoka.

The soldier had heard of the Internet, but he didn't know what it was. When Tsuneoka mentioned it to him, he was eager to see it, but the phone wasn't signed up to receive the carrier's GPRS data service for accessing the Internet.

"I called the customer care number and activated the phone," he said. Soon after he had the captor's phone configured for Internet access.

"Once I told them I was able to access, they said 'how do you use it?', 'can we see Al Jazeera?'." Tsuneoka said he explained they just needed to type "Al Jazeera" into Google search to access the Qatar-based TV news network's website.

"But if you are going to do anything, you should use Twitter," he said he told them. "They asked what that was. And I told them that if you write something on it, then you can reach many Japanese journalists. So they said, 'try it'."

"I don't think they realize they were tricked," he said.

Martyn Williams covers Japan and general technology breaking news for The IDG News Service. Follow Martyn on Twitter at @martyn_williams. Martyn's e-mail address is martyn_williams@idg.com