Police investigating online threats against a councillor who is set to become Northern Ireland’s first black mayor have arrested a man.

Lilian Seenoi-Barr, originally from Kenya, has been selected by the SDLP to be the next first citizen of Derry City and Strabane District Council.

A 30-year-old man attended Strand Road police station in Londonderry on Sunday and was detained on suspicion of harassment, threats to kill and improper use of a public electronic communications network.

Police are treating the alleged offences as a racially motivated hate crime.

The man remained in custody on Sunday evening.

A PSNI statement assured the public that police took reports of online threats and harassment extremely seriously.

Earlier on Sunday, Ms Seenoi-Barr said the racist abuse and death threats directed at her since her selection was announced had made her more determined to succeed in the role.

Her party leader Colum Eastwood has condemned the racist abuse and what he described as “very serious death threats”.

The councillor said on Sunday morning that she wanted to focus on the many people who had reacted positively to her selection.

“My family is the one that is feeling it more than myself, I’m used to it,” Ms Seenoi-Barr said of the abuse and threats.

“Since I put myself forward to represent my community, since I came to this country, I’ve been experiencing racism but obviously it’s (the recent abuse) beyond what I have been experiencing.

“The death threats have been extremely hurtful to my family and to myself too, but I’m more focused on the positives. I have had enormous support across the island – community organisations, politicians who have reached out and stood in solidarity. That is the Derry I know, the Ireland I know, and that’s what I want to focus on.”

She told BBC NI’s Sunday Politics programme that she had not had second thoughts about taking up the post.

“Absolutely, no,” she said.

“I think it has actually made me more determined because we need to be represented, we need a more inclusive and progressive society and the majority of people, particularly in my city, stand with me.

“I have never enjoyed so much support than I have enjoyed the last few weeks from everyone across the city. When I’m walking on the street, people are hugging me and congratulating me. It’s something that they want and they want to celebrate it and I’m really looking forward to showcasing the best of our city.

“Many of the abuse… are not from Derry, although some are. We’re not a perfect country and there is so much that is going on.

“My focus is really to show that we are a united community, we can be a united community and everyone within our city and district can be represented by anyone, regardless of the colour of their skin. And we have the opportunity to do that together.”

The process used by the SDLP to select her as mayor has also caused discontent within SDLP ranks in Londonderry, with two councillors resigning amid claims it was undemocratic.

Mr Eastwood has conceded the party had lessons to learn over how it communicated a new policy, introduced last year, on selecting mayoral candidates.

But he has insisted that Ms Seenoi-Barr was the “stand-out” candidate to become mayor.

On Sunday, Ms Seenoi-Barr said: “It’s obviously disappointing that two of my colleagues who I have worked with the last three years since I got to council decided to resign.

“But I’m honestly focused on the way forward, I’m focused on serving my community.”