Israel's Mossad espionage agency has invited would-be spies to crack a riddle in a creative "help wanted" ad.

Mossad is the acronym for "HaMossad leModiʿin uleTafkidim Meyuḥadim", the Agency for Intelligence and Special Tasks, and is responsible for intelligence collection, covert operations and counter-terrorism operations.

The world-renowned intelligence group has posted a riddle on its website. Anyone solving the puzzle is fast-tracked for employment.

Thursday marks the third straight year that the Mossad has published an online challenge in order to attract Israel's top talent. The Mossad has put a strong emphasis at attracting cyber wizards from Israel's hi-tech industry, which insiders say has been a challenge due to the high salaries such employees can earn in the private sector.

In December, the Mossad joined Israel's other security agencies in opening a Facebook page for recruiting future secret agents.

Until now, the Mossad only recruited through its website, which is published in Hebrew, English, French, Russian, English, Arabic and Persian. Israel's Shin Bet internal security service and the Israel Police already have Facebook pages for recruitment purposes.

"Publicizing our jobs on Facebook will enable us to recruit more efficiently, with access to a wider population, in order to choose the most suitable candidates," said the Mossad in a statement.

The Mossad has been dealing with increasing challenges in recent years. The Mossad constantly recruits candidates in wide variety of fields, including intelligence, technology, cyber, computing, economics and logistics and its website also offers positions for students and people with special needs.

In July, the Mossad announced that they were looking for an experienced tailor.

"We require a fabric and leather tailor to create and sew high-quality leather products. The applicant must have at least three years experience in leather tailoring and tailoring with other materials as well," reads the notice on its careers page.