Sinclair Broadcast Group, a right-leaning broadcasting company, reportedly provided more than 100 of its local TV news stations with a "must run" segment that included a staunch defense of the US's use of tear gas against migrants at the US-Mexico border on Sunday.

President Donald Trump has strongly defended US Customs and Border Protection agents' use of tear gas against the migrants, many of whom are part of a caravan traveling to the US to seek asylum.

In the segment, Sinclair's chief political analyst, Boris Epshteyn, a former Trump administration staffer, called the migrant caravan "an invasion of our country."

Reports on Tuesday said Sinclair Broadcast Group gave over 100 of its local news outlets a "must run" segment that included a defense of the US's use of tear gas against a group of migrants, including children, at the US-Mexico border on Sunday.

Sinclair Broadcast Group, a right-leaning broadcasting company based in Maryland, is the largest TV-station owner in the United States. The Seattle Post-Intelligencer reported that "the company distributes 'must-run' segments to its newsrooms, requiring they air them within 48 hours." They often appear in the middle of otherwise objective local news broadcasts and "typically feature conservative commentary, including a recurring segment" from Boris Epshteyn, a former Trump administration official who now serves as Sinclair's chief political analyst.

According to Media Matters for America, a nonprofit that monitors conservative media, Sinclair forced about 100 local news networks to air Epshteyn's defense of US Customs and Border Protection agents' using tear gas on the migrants, many of whom are part of a caravan traveling to the US to seek asylum.

The Daily Beast reported that the latest "must-run" segment began with Epshteyn saying that "the migrant crisis on our southern border has greatly escalated."

According to The Daily Beast, footage from the confrontation plays, and Epshteyn says: "Dozens of migrants attacked US border enforcement by throwing rocks and bottles. Ultimately, American authorities had to use tear gas to stop the attacks."

Media Matters quoted Epshteyn as saying:

"The fact of the matter is that this is an attempted invasion of our country. Period. Our border must remain intact and secure. It is not a partisan position to believe that our immigration system is broken and needs to be fixed. However, it unfortunately appears that there are many on the left who believe it is wrong to defend our country and abide by the rule of law. I would bet that many of those same people live behind walls and locked doors but do not want to afford the same benefit to our country as a whole."

In the face of growing anger over the incident, President Donald Trump has strongly defended the agents' use of the tear gas.

"They were being rushed by some very tough people, and they used tear gas," Trump said on Monday, according to The Associated Press. "Here's the bottom line: Nobody is coming into our country unless they come in legally."

At a roundtable in Mississippi later in the day, Trump seemed to acknowledge that children were affected but blame poor parenting, the AP reported.

"Why is a parent running up into an area where they know the tear gas is forming and it's going to be formed and they were running up with a child?" he said.