Egypt's army condemned, in a statement late Saturday, what it said were "lies" used in favour of "terrorist organisations" staging attacks against police and army installations and personnel.
Three soldiers were killed and four others injured, the military spokesman announced, in a blast near a security checkpoint Saturday evening in Sheikh Zuweid, North Sinai.
Some media reports, however, claimed that a larger number of soldiers had fallen victim.
In response, army spokesman Mohamed Samir said on his official Facebook page that such news reports were "lies" used by terrorist organisations to "promote false victories" and hide their "heavy losses."
He denied other victim counts published by some media outlets, saying the armed forces announce "the true numbers" and protects its credibility with the Egyptian people.
The army also said it has been engaged in battles with militants Saturday in three areas south of Sheikh Zuweid, killing a number of militants and arresting others.
The Islamic State's Egypt affiliate, Sinai Province, claimed responsibility for the attack in a statement carried on social media websites.
On 1 July, Islamic State-affiliated militants launched multiple attacks against army and security forces in and around Sheikh Zuweid, leaving at least 21 soldiers dead.
In the past two weeks, the Egyptian army has been carrying out intense strikes against militant hideouts, which reportedly left more than 200 militants dead.