The Boston Globe was one of the first to report of "a suspect" in custody on Wednesday in connection to the Boston Marathon bombing on Monday, and the publication noted via Twitter a federal courthouse was evacuated, according to people at the scene.

"Man left locked car at valet. Gas cans in back, according to official source," the publication tweeted at 12:12 p.m. local time, followed by the following: "Federal courthouse evacuated; hundreds outside. People are being pushed back from building. Coast Guard and police boats in water."

A evacuation followed a Code Red announcement, ABC News reported. Boston police said a bomb threat was made, and the bomb squad and fire department are on the scene. The courthouse was reportedly surrounded by media outlets after news surfaced of an appearance by the suspect in the marathon bombings.

A live video feed of the scene outside the federal courthouse in Boston has been made available by MyFoxBoston.com.

A federal law enforcement source told CNN's John King on Wednesday that "significant progress" in the investigation has been made. The FBI officially confimed in a statement that no arrests had been made, and one law enforcement source told the network "anyone who says 'arrest' is ahead of themselves."

"Contrary to widespread reporting, no arrest has been made in connection with the Boston Marathon attack," the FBI said.

Three died on Monday as a result of the two explosions at the Boston Marathon, and their indentities were revealed on Tuesday.

Twenty-nine-year-old Krystle M. Campbell from Medford, Mass., died at the race, which she attended to support her boyfriend who was running in the marathon. Campbell was at the finish line when the first bomb went off at 2:50 p.m. on Monday.

Boston University graduate student Lingzi Lu was the last victim to be identified on Tuesday. Lu was named by The Senyang Evening News, Chinas' state-run newspaper, and her father confirmed her death.

Martin Richard was the youngest of the three victims to die on Monday. At the age of 8, he was waiting to greet his father at the Boston Marathon with his mother, Denise Martin, and 6-year-old sister. Martin had stepped off the sidewalk to greet his father Bill Richard- a local community organizer- as the latter was approaching the tail end of the race.