A drone strike in Syria reportedly killed a married US jihadi couple who had pledged allegiance to the Islamic State and worked to recruit new fighters.

The husband and wife team were identified as Abu Issa Al-Amriki and Umm Issa Al-Amrikiah in social media accounts linked to IS (Isis/Daesh). Neither their birth names nor home towns were revealed, though "Al-Amriki" usually refers to Americans.

The husband and wife "were hit in their house by the air strikes and they both attained shahada", or martyrdom, said one account in social media linked to IS, according to Fox News.

They were killed in late April, according to the Middle East Media Research Institute's Jihad and Terrorism Threat Monitor. It's not clear who launched the drone strike, though it could have been other Americans.

The female half of the team appeared to work particularly hard at making jihad appeal to women. One post reportedly read: "My account is for sisters only, so unless you menstruate do not message me." IS strictly limits socializing between men and women who aren't related.

Another post showed her holding what appeared to be a suicide belt and saying she hoped she could use it herself to kill "infidels". An estimated 150 Americans have travelled, or have attempted to travel, to Syria to join terror cells.