President Mohamed Morsi
has issued a three-day period of national mourning for those killed during Sunday's attack
by unknown assailants on Egyptian border guards in Sinai, confirmed presidential spokesman Yasser Ali on Monday.
In a press statement, Ali added that the president has vowed to honour the 16 "martyrs" and seven injured soldiers as well as promising to award the victims' families financial compensation.
The presidential spokesman went on to say that Egypt's national security, military and civilian intelligence together with specialised security forces are working "around the clock" to fully understand what happened. They are expected to announce the results of their investigations shortly.
Ali confirmed that it is not yet known whether Egyptians or foreigners were behind the attack.
This comes after an anonymous Egyptian security official was quoted by state-run news agency MENA, on Sunday, as saying that Islamist elements from the Gaza Strip entering Egypt via tunnels were responsible.
Ali also emphasised that following Morsi's Sunday meeting with head of the Supreme Council of the Armed Forces Field Marshal Hussein Tantawi, Chief of Staff Sami Anan, newly-appointed Minister of Interior Ahmed Gamaleddin and Egyptian Intelligence chief Murad Mowafi, all procedures have been implemented to assure Egyptian control of the Sinai Peninsula.
According to media reports the Sunday evening assault involved a military vehicle, reportedly hijacked earlier, which exploded around 7pm. Others were injured after the attackers opened fire on them. No group has claimed responsibility for the attack.