As a freelance photographer he covered several areas of conflict: Afghanistan, Haiti, Pakistan and nearly all countries of the Near East (Iraq, Iran, Lebanon, Sudan, Libya, Syria, Israel and the Palestinian Territories).
In July 2012, Oerlemans and the British photographer John Cantlie were kidnapped in northern Syria and detained for one week.
Oerlemans had been scheduled to return home Monday, but was shot dead by snipers attached to the Libyan arm of Islamic State.
[...] The only consolation is that he was immediately dead, he did not suffer in any case.″[3] The Foreign Ministry of the Netherlands confirmed Oerlemans' death on Sunday, 2 October 2016.
Bert Koenders, the Dutch Foreign Minister, paid tribute to him, saying "Oerlemans was a journalist who went through where others stopped, driven to bring the news in pictures, especially in the trouble spots of the world.