Actor Peter Fonda apologized Wednesday afternoon for a threatening tweet in which he said Americans upset with the White House's separation of illegal-immigrant families 'should rip Barron Trump from his mother's arms and put him in a cage with pedophiles.'

The first lady's office conferred with U.S. Secret Service about the incident. The agency wouldn't say on Wednesday whether it had contacted the aging Oscar-winner directly.

Fonda issued a statement hours later, shortly after President Donald Trump signed an executive order forbidding the government from detaining children separately from the adults who brought them across the U.S.-Mexico border.

'I tweeted something highly inappropriate and vulgar about the president and his family in response to the devastating images I was seeing on television,' Fonda said.

'Like many Americans, I am very impassioned and distraught over the situation with children separated from their families at the border, but I went way too far. It was wrong and I should not have done it. I immediately regretted it and sincerely apologize to the family for what I said and any hurt my words have caused.'

'HE'S NOT HERE': Peter Fonda's assistant told DailyMail.com on Wednesday that the aging actor wasn't home – until he appeared outside his Pacific Palisades, California home – after the Oscar-winner draw international scrutiny by sending what he acknowledged was a 'highly inappropriate and vulgar' tweet about Melania Trump and her son Barron

The Secret Service was spurred to action on Wednesday, Melania's spokeswoman Stephanie Grisham confirmed, after Fonda wrote that Americans upset with the White House's separation of illegal-immigrant families 'should rip Barron Trump from his mother's arms and put him in a cage with pedophiles'

Barron is the only son of Melania and Donald Trump

Fonda has told his Twitter followers that President Trump's 12-year-old son Barron should be ripped from his mother's arms and put 'in a cage with pedophiles' in an expletive-laden rant about the border crisis

Mrs. Trump's spokeswoman Stephanie Grisham told DailyMail.com earlier in the day that Fonda's tweet was 'sick and irresponsible and USSS [U.S. Secret Service] has been notified.'

Secret Service is charged with a variety of specialized jobs including the security of the White House, the president, the first lady, their children, and all former first families.

Trump counselor Kellyanne Conway had a two-word reaction to Fonda's tweets: 'Beyond. Chilling.' Donald Trump Jr. 'liked' her tweet.

Don Jr. tweeted: 'As an FYI @SonyPictures has a movie with him dropping in a few days. I wonder if they will apply the same rules to @iamfonda that they did to @therealroseanne. I have a strange suspicion that they wont do anything. Please RT, we deserve an answer!'

A spokesman for Sony Pictures Classics, referring to the indie feature Boundaries which is set to open Friday, said: 'Peter Fonda’s comments are abhorrent, reckless and dangerous, and we condemn them completely. It is important to note that Mr. Fonda plays a very minor role in the film.

'To pull or alter this film at this point would unfairly penalize the filmmaker Shana Feste’s accomplishment, the many actors, crew members and other creative talent that worked hard on the project. We plan to open the film as scheduled this weekend, in a limited release of five theaters.'

Fonda ducked inside his Pacific Palisades, California, home and stayed silent when DailyMail.com approached him on Wednesday.

Instead the job of commenting was left to an assistant who had claimed at first that the actor wasn’t at home – and insisted: 'He’s not here and we’re not going to answer the door.'

The red-headed woman added then: 'No you can’t [ask about Barron Trump]. No, we have no comment.'

Fonda, who splits his time between Los Angeles and a second home in Paradise, Montana, lives in a large cream-painted gated home in the upmarket Pacific Palisades enclave.

Fonda lives in the Pacific Palisades, California enclave in a gated home; he declined comment when DailyMail.com approached him Wednesday

By tweeting what amounted to a threat against a member of the first family, Fonda attracted the attention of U.S. Secret Service, which is charged with protecting the president and his household

Counselor to the President Kellyanne Conway said Fonda's tweets were 'Beyond. Chilling.' Donald Trump Jr. 'liked' the post

The 'Easy Rider' star did not appear to issue an apology to U.S. Immigration and Customs Enforcement officers. In his tweetstorm, he had said 'we should hack the system' and 'get the addresses of ICE agents' to 'surround their homes' and 'find out what schools their children go to and surround the schools.'

Branding President Trump a 'f****** monster', he added: 'We need to scare the f*** out of [border agents]! Need to make their children worry now.'

And in addition for urging people to kidnap and abuse Barron Trump, he 78-year-old had called for 90 million people to take to the streets in protest at the government's decision to criminally prosecute illegal immigrants who jump the border.

He also referred earlier to presidential adviser Stephen Miller as a 'pedophile.'

Fonda also called Miller, who is Jewish, 'Goebbels' in an apparent reference to Nazi propagandist Joseph Goebbels, an extreme anti-Semite who strongly supported the Holocaust and arranged the murder of his own children in 1945.

Melania and Barron are more often together than apart at the White House as she tries to give him as normal an upbringing as possible within the Secret Service 'bubble' where they're required to live

Fonda also called Miller, who is Jewish, 'Goebbels' in an apparent reference to Nazi propagandist Joseph Goebbels, an extreme anti-Semite who strongly supported the Holocaust and who arranged the murder of his own children in 1945

He also called for 90 million people to take to the streets in protest at the government's decision to criminally prosecute migrants who cross the US border illegally and separate them from their children

The Easy Rider star, who has more than 46,000 followers, also said 'we should hack the system' and 'get the addresses of ICE agents' to 'surround their homes' and 'find out what schools their children go to and surround the schools'

In previous tweets on Tuesday, he said that White House Press Secretary Sarah Sanders should be deported 'to Arkansas.'

He also said her children should be given to Stephen Miller.

Fonda said Secretary of Homeland Security Kristjen Nielsen, meanwhile, should be 'put in a cage and poked at by passersby' as well as 'pilloried in Lafayette Square naked and whipped by passersby while being filmed for posterity.'

It comes after it was revealed that Trump administration officials have been sending babies and other young children separated from their parents at the US-Mexico border to at least three 'tender age' shelters in South Texas.

Lawyers and medical providers who have visited the Rio Grande Valley shelters described play rooms of crying preschool-age children in crisis.

A two-year-old Honduran cries as her mother is searched and detained near the US-Mexico border on June 12. She had illegally crossed the Rio Grande on a raft to reach Texas

A Mission Police Department officer, and a US Border Patrol agent watch over a group of Central American asylum seekers before taking them into custody in McAllen, Texas

The inside of a dormitory at the Tornillo facility, a shelter for children of detained migrants, is seen in this photo provided by the US Department of Health and Human Services, in Texas

The Trump administration has been accused of using children as political pawns in its attempts to negotiate on border security

The government also plans to open a fourth shelter to house hundreds of young migrant children in Houston, where city leaders denounced the move Tuesday.

Since the White House announced its zero tolerance policy in early May, more than 2,300 children have been taken from their parents at the US-Mexico border, resulting in a new influx of young children requiring government care.

The government has faced withering critiques over images of some of the children in cages inside US Border Patrol processing stations.