A suspected white nationalist has been arrested after allegedly threatening to carry out a mass shooting at a Jewish community centre in Ohio.

Police said James Reardon Jr posted a video on Instagram of a man shooting a semi-automatic rifle with the caption: "Police identified the Youngstown Jewish Family Community shooter as local white nationalist Seamus O'Rearedon."

The post, which authorities said came from Mr Reardon's Instagram account, @ira_seamus, tagged the the Jewish Community Centre of Youngstown. Seamus is the Irish form of James.

The 20-year-old was arrested at his home in Mahoning County village on Saturday on telecommunications harassment and aggravated menacing charges.

Rounds of ammunition, semi-automatic weapons and antisemitic information were found at his home, New Middletown police said.

Andy Lipkin, Youngstown Area Jewish Federation's executive vice president, said they were aware of the incident and were working with police.

"I want to stress that we know of no other threat to the Jewish community or to any of our agencies at this point it time," he said in a statement posted on the organisation's website .

"Nonetheless, I have directed that we maintain the additional level of security for the near future."

Mr Reardon's arrest came just two weeks after a suspected white supremacist shot dead 22 people at a Walmart in El Paso, Texas, in an attack aimed at the city's Hispanic population.