If you've watched television lately, you've seen the ads -- Congressman Marsha Blackburn's attack on comments made by Governor Phil Bredesen about an immigrant caravan and his defense of his record of border security.

The ads make many claims, but what is the truth?

Blackburn's 30-second ad titled "Caravan" begins by saying "a caravan of 14 thousand illegal immigrants is marching on America."

The fact-checking website Politifact says that number comes from one report in a Mexican newspaper.

On Friday, the United Nations said the number of migrants is closer to 7,000 and about a third of them are children.

Since then, both the Associated Press and USA Today have reported the number is down to fewer than 4,000.

The AP said the migrants are still more than 800 miles from Southern Texas, traveling about 40 miles per day on foot.

The Blackburn ad also uses a piece of video from Bredesen talking about the migrant caravan.

In the ad, Bredesen says "A few thousand very poor people is not a threat to our security."

Bredesen did say those words, but there was more to the quote.

He told WCYB, "We are the strongest country in the world. A few thousand very poor people going to our border are not a threat to our security."

The Blackburn ad also claims there are gang members, Middle Easterners, and terrorists in the caravan.

A spokesman for the Department of Homeland Security said there are gang members and individuals with criminal histories in the caravan. He said there are also people from the Middle East traveling through Mexico to the U.S.

When asked by reporters about terrorists in the caravan, President Trump said, "There's no proof of anything. There's no proof of anything. But there very well could be."

On Wednesday, Bredesen released his own ad about his record on immigration as governor.

It says, "Governor Bredesen took immediate action and sent 1,600 National Guard volunteers to the border."

In 2006, 10News reported on the deployment of 1,600 Tennessee troops.

The ad goes on to say "Governor Bredesen went to the border to support them."

That happened too. A WBIR reporter traveled to Arizona to cover his visit.