It urged respecting principles declared in international agreements that ban the attacking of innocents and consider the abductions as contradictory to the principles of human rights.
Meanwhile, as the Syrian war ground on, the United Nations said Wednesday that Lakhdar Brahimi, the U.N.-Arab League envoy to Syria, would meet Friday with Russian Deputy Foreign Minister Mikhail Bogdanov and U.S. Deputy Secretary of State William Burns.
The meeting, to be held in Geneva, Switzerland, would be "aimed at furthering their discussions to arrive at a political solution to the crisis in Syria," a spokesman for U.N. Secretary-General Ban Ki-moon said.
But on the ground, blood kept flowing.
A car bomb rocked the Damascus suburb of Modamieyah on Wednesday, with reports of deaths and injuries, said the Syrian Observatory for Human Rights, an activist group.
Fighting also continued in the Taftanaz area of northern Syria, where rebels were engaged in a battle for a key Syrian air base.
Al-Nusra Front, a militant group that the United States has designated as a terrorist movement, is among three rebel factions attacking the base in Idlib province, rebels have said.
Elsewhere, wintry weather appeared to put a brake on some military operations.