(The Hill) — The father of a boy who died in the 2018 shooting at Marjory Stoneman Douglas High School climbed a construction crane near the White House on Monday in an effort to encourage action on gun violence.

Manuel Oliver — the father of Joaquin Oliver, who died in the fatal shooting exactly four years ago — climbed the construction crane early Monday before unveiling a banner with an image of Joaquin, according to Fox 5 DC.

He was later taken into custody, according to a statement from the Metropolitan Police Department, along with two other individuals — one of whom was allegedly also on the crane. Authorities, however, did not identify the other individuals.

Manuel posted a video on Twitter on Monday morning of himself on top of the crane. The father’s words are difficult to understand because of the wind blowing in the background.

In one part, however, he is heard saying “so the whole world will listen to Joaquin today.”

“He has a very important message. I asked for a meeting with Joe Biden a month ago. Never got that meeting,” he added.

Patricia Oliver, the wife of Manuel and mother of Joaquin, told Fox 5 DC that she and her husband were “trying to give Joaquin one more” chance for his voice to be heard.

She said Manuel is trying to send a message to President Joe Biden, urging him to take action on gun violence.

“Joaquin is up there, at the crane, because Manuel has to represent him. So he’s trying to send a message to Mr. Biden. Mr. Biden, we have lost 45,000 people since your administration is started,” she said, looking straight into the camera.

Patricia said she and her husband are launching a website called ShockMarket.org “where you can see in live time how many people we’ve been seeing that they been losing their life.”

She pleaded with Biden to “take action.”

“Please, please take action. Today is being my fourth year without Joaquin. But Joaquin is today there sending a message. Please listen to him. You said it, you’re gonna do something. Take action,” she added.

Fourteen students and three educators were fatally shot on Feb. 14, 2018, when a gunman opened fire at Marjory Stoneman Douglas High School in Parkland, Fla., marking the deadliest high school shooting in the country. The shooter, who at the time was a student at the school, pleaded guilty to all charges connected to the incident in October.

The 2018 shooting gave rise to the March for Our Lives movement, an effort that advocates for ending gun violence.

Democrats have tried to enact gun control reform a number of times in the aftermath of the 2018 shooting, though they have remained largely unsuccessful.

The latest attempt was in Decemberx, when Senate Democrats tried to proceed on legislation the House passed in March that seeks to expand background checks. Sen. Chuck Grassley (R-Iowa), however, blocked the request.

Biden used Monday’s four-year anniversary of the deadly shooting as an opportunity to press Congress to enact measures addressing gun violence in the U.S. He wrote in a statement that Congress “must do much more” to combat violent crime in the U.S.

The Metropolitan Police Department said it responded to the 700 block of 15th St. NW in Washington, D.C. at approximately 5:40 a.m. on reports on unwanted individuals. Upon arrival, authorities apprehended one individual, then took the two individuals located on the crane into custody.

All three individuals were arrested at the scene. Their identities have not been revealed.

The Hill has reached out to the White House for comment.