Washington: The Islamic State of Iraq and Syria (ISIS) may be hogging the headlines but the Syrian reincarnation of the old al Qaeda is being considered a more serious threat to the United States, a report said.
According to the CBS News, sources revealed that operatives and explosives experts from Osama bin Laden`s old al Qaeda terror network, now called "Khorasan", may again present an immediate threat to the US homeland security.
Sources also conceded that due to the emerging threat in Syria, where hardened terrorists loyal to al Qaeda leader Ayman al-Zawahri are working on new, hard-to-detect bombs.
The report said that the outfit is probably using US and European passport holders to smuggle explosives onto airplanes easily.
Unlike ISIS, which is caught in its fight for territory, Khorasan is devising fresh plans to target US aviation.
It is also recruiting Westerners in Syria, some of whom have joined the Syrian front of the al Qaeda in the country, known as the Al-Nusra.