Hamas arrests Gazan after Zoom call with Israeli activists
"Establishing any activity or communication with the Israeli occupation under any excuse is a crime punishable by law, and is treason against our people," a statement added.
Aman's Facebook page said he was a member of a group that describes itself politically independent in the Gaza Strip, which Hamas has controlled since 2007.
A link shared online shows Aman, and other individuals, speaking via the videoconferencing group Zoom, with people believed to be members of Israeli left-wing groups.
Hamas seized Gaza from the internationally recognised Palestinian government in a 2007 near civil war and has fought three wars with Israel since.
All contact with Israelis is banned and those accused of spying for Israel have been put to death.
Read more: Israel considers sending ventilators to Gaza in exchange for release of soldiers held by Hamas
Hamas is considered a terrorist organisation by many Western governments.