Making phone calls close to military checkpoints is not advisable, a senior Nigerian military official said on Monday.
"It is a security measure for when you are approaching a checkpoint," he said, "you don't make phone calls," said Major-General Usman Mohammed, Nigerian Army's head of Civil-Military Affairs said on Channels Television's Sunrise Daily on Monday.
"The tendency is that if you are making a phone call, you might be communicating with some bad guys. Or you may use that particular device to set up some certain devices.
Mohammed said the rule is not peculiar to Nigeria.
"It is everywhere; people who have traveled abroad know that you don't make phone calls when approaching a checkpoint."
Nigeria's internal security has been under pressure for most of the decade, with Boko Haram insurgency, farmers-herders clashes, kidnapping and violent robberies all stretching the country's security agencies.
The country was ranked as the third country most impacted by terrorism on the 2019 Global Terrorism Index.