The state of emergency imposed in northeastern Nigeria to crush Boko Haram Islamists has ended, the lower house of parliament said Thursday, announcing that it had rejected a government request to extend the special powers.

The development came on a day that saw police fire tear gas inside the parliament building, apparently targeting the speaker of the House of Representatives, Aminu Tambuwal, who defected to the opposition last month.

Nigerian police fired teargas inside the parliament complex on Thursday, apparently trying to block opposition lawmakers, including the speaker of the lower house, from entering the building for a key security vote.

Members of the House of Representatives had been scheduled to vote on a government request to extend emergency rule in the northeast region hit hardest by Boko Haram militants.

Nigerian Islamist extremists Boko Haram are intensifying attacks in neighboring Cameroon, targeting new villages with increasingly sophisticated weapons, as the army fears more violence in the approaching dry season.

"We're convinced that the establishment of a 'caliphate' (by Boko Haram) is aimed not only at Nigeria but also at Cameroon," Leopold Nlate Ebale, commander for an elite battalion in the border zone, told Agence France Presse.

Nigerian troops, backed by civilian vigilantes and local hunters, have reclaimed two towns seized by Boko Haram Islamists last week, residents and a local fighter said Wednesday.

The re-capture of the towns of Gombi and Hong on Tuesday was the latest success the military has recorded against Boko Haram in recent days, they claimed.

Nigeria's main opposition party on Wednesday accused the government of playing politics with Boko Haram, as it held its first major election rally.

"The PDP (Peoples Democratic Party) is sacrificing the lives of our brothers, of our sisters, of our children for very selfish political ends," said the All Progressives Congress national chairman, John Oyegun.

An angry mob on Tuesday beat a suspected would-be suicide bomber to death after he was accosted at a bus station in northeast Nigeria, police and witnesses said.

The man was stopped as he tried to get into the bus station in the Gombe state capital, Gombe city, where at least eight people were killed in a series of blasts at the same location last month.

Emergency rule to tackle Boko Haram in northeast Nigeria has been an outright failure, senators from the affected regions said Tuesday, as the government sought to extend the powers.

President Goodluck Jonathan submitted a request to the upper chamber of parliament to grant approval for the special measures in Yobe, Borno and Adamawa states for a further six months -- a timeframe that would extend beyond February elections.

Boko Haram is using female suicide bombers to sow wider panic and fear across Nigeria as well as gain greater publicity for its cause, experts said, after two fresh attacks in a week.

The attacks, in Azare in the northeastern state of Bauchi and the Niger state town of Kontagora in the northwest, came after four attacks in a week in the northern city of Kano in July.

The Nigerian army said Sunday it had recaptured the northeastern town of Chibok, where Islamic militants abducted more than 200 schoolgirls in April, provoking a wave of global outrage.

Control of Chibok is crucial to the reputation of the government of President Goodluck Jonathan and the military, which have both come under fire at home and abroad for their failure to rescue the girls.

A female suicide bomber blew herself up Sunday at a mobile phone market in northeast Nigeria, killing several people, witnesses said.

The attack happened in the town of Azare in Bauchi state, which neighbors the three states worst hit by attacks from Boko Haram Islamists.