One arrested in connection with US serial bomb packages

US authorities have arrested at least one person in Florida in connection with the series of explosives-laden suspicious packages sent to several present and former high-ranking officials including former US president Barack Obama, former vice president Joe Biden and former secretary of state Hillary Clinton.

"We can confirm one person is in custody," Justice Department spokesperson Sarah Isgur Flores said. The department of justice is scheduled to hold a news conference later.

Since Monday, homemade bombs and other suspected explosive devices have been addressed to Obama, Clinton, Hollywood actor Robert De Niro and a slew of figures disliked by the president's supporters.

At a White House event, Trump promised to prosecute those responsible to the fullest extent of the law.

In his remarks, Trump expressed amazement that the arrest happened so quickly, as it was similar to finding "a needle in a haystack".

Multiple news outlets identified the suspect as Cesar Sayoc, 50, and a resident of Florida. The suspect is said to have a criminal history and ties to New York.

Earlier, Trump tweeted that the bomb scare is having an adverse impact on the electoral prospects of his Republican party ahead of the November 6 mid-term polls.

"Republicans are doing so well in early voting, and at the polls, and now this 'Bomb' stuff happens and the momentum greatly slows - news not talking politics. Very unfortunate, what is going on. Republicans, go out and vote!" Trump tweeted.