Thailand's foreign ministry said on Saturday that Hamas was still holding 20 Thai citizens after freeing 10 from Gaza.
The freed hostages had been moved to Israel via Egypt and would spend 48 hours in the hospital before returning home, the ministry said.
"There are now an estimated 20 Thai nationals who remain abducted," it said in a statement. "We sincerely hope the remaining hostages will be treated humanely and released safely as soon as possible."
The only Thai woman known to be held by Hamas was among those released.
News agencies including Reuters cited Thai sources as saying that the deal was separate to the hostage release and pause in fighting agreed by Israel and Hamas.
Thailand's foreign ministry thanked the governments of Egypt, Iran, Israel and Qatar, the International Committee of the Red Cross and others for the "immense efforts" that led to the release.