DUBAI (Reuters) - Egypt netted just $500 million in tourism revenue in the first quarter of 2016, down from $1.5 billion a year earlier, a tourism ministry adviser told Reuters, highlighting the country's struggle to kickstart a key dollar-earning industry.

Egypt's tourism industry, a cornerstone of the economy and critical source of hard currency, has been struggling to rebound after the political and economic upheaval triggered by the 2011 uprising that ended Hosni Mubarak's 30-year rule.

Tourism revenue has also taken a heavy hit since a Russian plane crashed in the Sinai last October, killing all 224 people on board in what President Abdel Fattah al-Sisi called an act of terrorism. Islamic State said it planted a bomb on board.

More than 14.7 million tourists visited Egypt in 2010, dropping to 9.8 million in 2011.

In the first quarter of 2016 just 1.2 million tourists travelled to Egypt, down from 2.2 million a year earlier, said economic adviser to the ministry of tourism Adla Ragab.

Egypt aims to attract 12 million tourists by the end of 2017 through a plan that includes increasing the presence of national carrier EgyptAir abroad, tourism minister Yehia Rashed said in a recent interview with Reuters.

"Many European airlines have halted flights to Sharm el-Sheikh. It’s too early to say what the long-term impact of the Russian plane crash will be," said an analyst at hotel industry consultants STR.

The torture of Italian graduate student Giulio Regeni, whose body was dumped on the side of a road in February, has also damaged Egypt's image abroad.

Egyptian intelligence and police sources told Reuters the police had custody of Regeni at some point before he died, but Egyptian officials have strongly denied any involvement in Regeni's death, saying he was never in their custody.

The Regeni case has brought allegations of widespread police brutality in Egypt under sharper focus. 

(Reporting by Matt Smith; Writing by Eric Knecht, editing by Ed Osmond)