A third-party candidate in Nigeria’s tightly contested presidential election has caused a major upset by winning in its biggest city, Lagos, results from state election officials show.

The Labour Party’s Peter Obi narrowly defeated the ruling party’s Bola Tinubu in his heartland, they say.

This is the first time since 1999 that a party backed by Mr Tinubu, a two-time Lagos governor, has not won the state.

But Mr Tinubu has won three of the five other states declared so far.

He also won in his south-western strongholds of Ondo, Ekiti and Kwara, narrowly losing to Atiku Abubakar of the main opposition Peoples Democratic Party (PDP) in Osun state.

Mr Abubakar has also narrowly won the presidential election in Katsina, the home state of outgoing President Muhammadu Buhari.

The results from Ekiti, Kwara, Ondo and Osun have all been confirmed by the head of the Independent National Electoral Commission (Inec) at its headquarters in the capital, Abuja, however the other results remain provisional.

Mr Obi’s apparent victory in Lagos, though a major breakthrough for a third-party candidate, is not necessarily a huge surprise. The city is home to many young, educated people, as well as a large Igbo community – all groups widely seen as backing his presidential bid.

But with 30 states and the capital, Abuja, still to declare, it remains far too soon who might be elected Nigeria’s next president.