Administrative lapses, violence and deep-seated suspicions continue to plague Nigeria's census efforts. The organizers are under a lot of pressure to deliver, with only three days left to complete the census.
The authorities have asked Nigerians to stay at home on Friday and Saturday to facilitate the head count, which has been bogged down by administrative lapses.
In most communities across Nigeria, census officials are only now beginning the count, two days later than they were supposed to begin.
The slow pace of the process has prompted calls for the census to be extended by a few more days. But senior census officials are optimistic they will complete the exercise within the five-day period.
"We have started on a good footing, if I can say so myself," said Dotun Oduneye, the census commissioner for Abuja. "The first day is usually the roughest, and things are stabilizing now. People are in the field, working round the clock, and people are monitoring. I believe we will complete the exercise in the allotted time. And, tomorrow and Saturday are restricted days."
Observers say the credibility of the census is also being threatened by heightened political tension ahead of elections next year.
Nigeria has about 250 ethnic groups, each demanding a voice in the politics of the country.
For the second day running, police and separatists clashed Wednesday in the southeast. Field workers have been attacked. Hundreds of disgruntled census workers have disappeared with their materials.
Ibrahim Musa, of a civil society group based in Abuja, says the credibility of the exercise is already in very serious doubt.
"Previous exercises will even be more credible, more acceptable to Nigerians, because Nigerians believe that there is a hidden agenda for the exercise at this particular period in time," he said. "The government, if it is serious, should have done the exercise long before now, so that Nigerians will not associate it with the third term that the government is pushing. People have not been properly trained, and people who had been trained have been substituted with people who were not trained. Everything is not done in a manner that will bring credible result."
Nigeria, regarded as Africa's most populous nation, relies on estimated figures as a result of difficulties with previous attempts to determine its actual population.
Four previous censuses were marred by controversy.