The investigation is still open, and the perpetrators still at large, the police told the online Premium Times newspaper.
The mace is a symbol of the authority of the legislature, and it usually lies on the table in front of the senate president; without it in place, decisions cannot be made.
Though maces are used in similar symbolic capacities all around the world, in Nigeria it is a particularly potent symbol of governance: Outside the National Assembly, Nigeria's legislature that houses the senate, there is a giant statue of a raised fist holding a golden mace.
Nigerian lawmakers had expressed outrage Wednesday over the theft of the mace. “This action is an act of treason, as it is an attempt to overthrow a branch of the federal government of Nigeria by force and it must be treated as such,” Senate media and public affairs chairman Aliyu Sabi Abdullahi in a statement.
Within Nigeria, most of the suspicion fell upon Sen. Ovie Omo-Agege, who had only recently been suspended because of comments made during a debate over electoral reform ahead of next year's presidential election. As Omo-Agege was placed under arrest Wednesday afternoon, he told reporters: “I can't be under arrest; for what purpose?”
Nigerian media reports that the senator, despite his suspension, was with the mace thief when they entered the National Assembly.
Videos from the scene show a number of men pushing past security guards inside the building. In some videos, men can be seen lying on the floor, apparently injured. In his statement, Sabi Abdullahi said that some security staff at the National Assembly had been injured in the raid, which had lasted only a couple of minutes.
Politically motivated thefts have a long history in Nigeria. In a column for the Vanguard newspaper, Mike Ebonugwo wrote that “in the frequent power and leadership succession struggles over the years, control of the legislative arm was usually paramount.”
Ebonugwo wrote that in 1965, one senator “was said to have seized the mace which he wielded like a weapon to attack the Speaker and other parliamentarians.”
In this week's incident, however, the disruption was only temporary. The senate had a spare ceremonial mace that was used to restart proceedings 15 minutes after the intruders had left. According to the National Assembly, the senate was able to pass six bills for a second reading that afternoon.
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