Colin Kaepernick spotted in Houston during football drill

HOUSTON, Texas (KTRK) -- Controversial NFL free agent Colin Kaepernick was captured on video in Houston on Thursday engaged in throwing drills.

Yahoo Sports reporter Charles Robinson first reported on Kaepernick's workout, recording on the former 49er throwing in a simulation.

According to Robinson, this is the first time since he hit the free agency market in 2017 that he was seen throwing. Robinson reported Kaepernick went through the workout for 90 minutes.

It was immediately unclear the reason for his workout taking place in Houston.

The Houston Texans reportedly said they were unaware of Kaepernick's workout. In addition, it didn't appear that any NFL team was in attendance, according to Robinson.

In the evening, Kaepernick's visit to Houston led him to the Houston Museum of African-American Culture. The museum's Instagram account showed him dressed in black and visiting with a couple of fans.

Kaepernick is a polarizing figure in professional sports after he began kneeling during the National Anthem during his time in San Francisco. His gesture, which was a way to peacefully protest social injustice in the country, spread to other players and teams in the NFL.

The kneeling also drew detractors from other players, pundits, and President Trump, citing perceived disrespect for the U.S. flag.

Kaepernick has yet to be signed by a team since early in 2017.