More than two years after Boko Haram abducted 276 girls form a school in Nigeria, advocates remain hopeful for their return.
On Thursday, hundreds of people marched in cities in Nigeria demanding the safe return of the girls.
In the middle of the night on April 14, 2014, the Islamic terrorists attacked the Chibok Government Secondary School and kidnapped girls between 11 and 17 years old.
Several girls escaped, but more than 200 are still missing. Boko Haram reportedly wants millions of dollars in exchange for their freedom.
On Wednesday, CNN obtained a video showing 15 captives pleading with the Nigerian government to cooperate with Boko Haram. According to Nigerian officials, the government is currently taking part in negotiations for the girls' release.
According to WorldMag.com, two years ago when the abduction happened, the U.S. military sent a team of advisers to help the Nigerian government find the girls. U.S. and British drones spotted a group of about 80 girls, but the Nigerian government didn't act on the intelligence.
Advocates, including Rep. Frederica Wilson, D-Fla., and Rep. Shelia Jackson Lee, D-Texas, believe the United States still must play a role in bringing the girls home.
"I believe they are still alive and Boko Haram is holding these girls with the express purpose of bribery," Wilson said. "We will never give up until we bring back our girls."