Suspect arrested in Florida over 12 bombs, suspicious packages

US investigators have arrested a suspect in Florida in connection with 12 suspicious packages and pipe bombs sent to critics of Donald Trump in a days-long spree that has inflamed the United States ahead of key midterm elections.

The Republican commander-in-chief congratulated law enforcement Friday for what he called an "incredible, incredible job" as US media identified the suspect as Cesar Sayoc, a 56-year-old man with a criminal history.

"These terrorizing acts are despicable and have no place in our country," Trump told an event at the White House, confirming a suspect had been apprehended following an FBI-led nationwide manhunt mobilizing hundreds of agents.

"But the bottom line is Americans must unify and we must show the world that we are united together in peace and love and harmony as fellow American citizens," the president added.