UPDATE 2: Sheikh Nasser and colleagues laid to rest following funeral prayers.
Funeral prayers were held on Tuesday for UAE president's brother, who died the previous evening in a tragic helicopter accident over the Arabian Gulf.
Sheikh Nasser bin Zayed Al Nahyan and an unspecified number of colleagues were killed when the helicopter carrying them crashed into the sea, according to state news agency Wam.
The prayers were held at the Sultan bin Zayed Mosque and attended by President Sheikh Khalifa bin Zayed Al Nahyan and Sheikh Mohammed bin Rashid Al Maktoum, vice president and prime minister of the UAE and ruler of Dubai.
UAE Supreme Council members and rulers, crown princes and deputy rulers of all seven emirates were also in attendance.
The deceased were laid to rest at the burial ground in Al Bateen in Abu Dhabi.
Throughout the day Sheikh Khalifa received messages of condolences from sheikhs from around the UAE and from leaders across the Arab world.
Sheikh Nasser's death will be marked by a three-day official mourning period.
Dubai, Sharjah, Umm Al Qaiwain, Ras Al-Khaimah, Ajman and Fujairah have all declared three days of mourning.
The Ministry of Presidential Affairs said ministries and government departments would remain closed during the morning period.
However a later statement from the Ministry of Cabinet Affairs said work in all government departments, the public sector and in the private sector would continue as normal with no closure of offices.