ISIS militants have abducted at least 90 men, women and children from Assyrian Christian villages in northeastern Syria, Reuters said on Tuesday based on reports by the British-based Syrian Observatory for Human Rights.

The terrorist organization, which refers to itself as the "Islamic State" and controls large swaths of territory across Iraq and Syria, carried out dawn raids on rural villages home to the ancient Christian minority west of Hasaka, a city mainly held by Kurds, the news service detailed.

Meanwhile, Syrian Kurdish militia were assisted by U.S.-led air strikes and Iraqi peshmerga as they launched two offensives against ISIS militants in northeast Syria on Sunday. The forces countering the terror group are trying to retake Hassakeh province, which is strategically important because it borders both Turkey and ISIS-controlled areas in Iraq, the BBC said.

ISIS did not confirm the kidnappings of the Christians, but the organization abducted several Assyrians last year in retaliation for some of them fighting alongside the Kurdish YPG militia. Most were released after long negotiations, the AP detailed.

Military experts told the news service that ISIS militants were trying to open a new front to relieve pressure after several losses. The organization was recently driven from the Syrian town of Kobani near the border with Turkey.

"(ISIS fighters) are losing in several areas, so they want to wage an attack on a new area," explained retired Jordanian Gen. Fayez Dwiri.

Kurdish forces, backed by other Syrian armed groups, in turn, have hunted ISIS's fighters as far as their provincial stronghold of Raqqa, 100 miles from Aleppo.

Assyrian Christians in the Nineveh Plains, a region to the north and east of the Iraqi city of Mosul, meanwhile, are building an army to stand up to the Sunni militants, USA Today noted. The fighters are determined to preserve their homeland, their history and their heritage, the newspaper detailed.

The so-called Nineveh Plains Protection Unit, or NPU, is a battalion of 350 to 500 men trained by Sons of Liberty International, a U.S.-led nonprofit aimed at "stepping in where governments in the international community have failed."