Former FBI agents have warned against jumping to conclusions about why mail bombs were sent to President Trump's political enemies.

While speculation about the reason the packages were mailed this week runs from an effort to murder the addressees to a "false flag" campaign to damage Republicans ahead of the midterm election, experienced investigators say it is is difficult to deduce much about the bombmaker or his or her motive based on available public details.

Often, they caution, motives are not what they at first appear.

[READ: Pipe bombs scare: Here's what we know]

“I wouldn't eliminate Republican leanings or Democratic leanings. The bottom line is, it is a political message that someone is sending out,” said 35-year FBI veteran James Wedick. "You have to ask, 'What message was being sent?'”

Brig Barker, who worked 21 years as an FBI agent, said in his career, suspects often had different motives than investigators first assumed. "Politically, it could be a Republican, it could be a Democrat, it could be an independent, it could be someone totally apolitical,” Barker said.

"You have to avoid going to the simple reasoning that it's straight-up politically motivated. And if it is politically motivated, this could be taking place from the Democratic side, trying to highlight something before the election — you just never know," he said.

At least nine packages were intercepted by authorities, most publicly reported Wednesday, including pipe bombs sent to former President Barack Obama and former Secretary of State Hillary Clinton. Trump's critics point to the sharp rhetoric he uses against opponents.

Former FBI agent and profiler David Gomez, who worked 28 years at the bureau, said he doesn't fault other experts for being reluctant to make political assumptions. But Gomez said it appears likely the person opposes the targeted politicians.

"Any investigation has to pursue all possibilities. But I don't think false flag would be the first," Gomez said.

"[The targets] are all people the president has identified as his political opponents, and used them to rally his base," Gomez said. "Logically, this person is probably someone who identifies with that base."

Experts are broadly optimistic that evidence associated with the bombs — none of which exploded on their own — will be valuable, but say seemingly tantalizing clues, such as the misspelling of targets’ names, may be strategic errors.

On many profiling points, the experts disagree. Gomez said that he suspects there was a single bombmaker who feels oppressed and seeking revenge. The lack of self-detonations could be sending a message of power, he said, especially if a part was voluntarily omitted.

Wedick, however, believes that multiple people may have been involved given the number of devices, and said he won’t rule out female participation. Although men are more likely to commit crimes, he said that he helped investigate various left-wing radicals in the 1970s who were tied to political violence, including Patty Hearst and Bernadine Dohrn.

"I’m thinking like we had in the '60s and '70s, we have some wayward people," he said.

Barker, who resists associating a political motive, recalled the murkiness of cases he worked as reason to keep an open mind. He cited an incorrect assumption that a bank robbery suspect was male. While working counter-terrorism probes, he said, neighbors would sometimes falsely report each other to the FBI as potential terrorists to settle unrelated scores.

“I had cases where we thought there was a political reason behind a campaign like this, and then you sit down the individual and you find out maybe they are mentally unstable, maybe they had personal issues, challenges unrelated to the political angle,” Barker said.

"We would go out, knock on the door and sit down with the suspect, and oftentimes the motive was not what you thought in the beginning," he said. "Sometimes investigations go on 5 years and then you finally sit down with the individual and find out it was motivated by something totally different than what you thought. Oftentimes the mistake is trying to pin it on a superficial motive that appears to be the go-to reasoning."

Although the term “false flag” often is associated with conspiratorial thinking, Barker said it “certainly does happen.”

There are some notable recent examples of terroristic threats triggering inaccurate public conclusions. Last year, Jewish Community Centers in the U.S. received hundreds of threatening phone calls, creating significant public concern about rising anti-Semitism. Authorities in Israel determined a local teenager was responsible.

As the mail bombs command pervasive news coverage, many experts weighed in on possible suspect profiles.

Former FBI profiler Mary Ellen O'Toole told "CBS This Morning" on Thursday that the suspect may have intentionally made spelling errors, and could have intentionally designed the devices not to explode.

Retired FBI profiler James Fitzgerald, who worked on the Unabomber mail-bomb case in the 1990s, said on Fox News Wednesday evening that a false-flag motive was conceivable.

"These devices were either made and sent by a right-wing guy who doesn't like the Dems — and we can't rule out international aspects to this, Russians messed with our 2016 elections just using Facebook, could they have done this? — but of course the other one is that false flag," Fitzgerald said.

The wave of suspicious packages started Monday when a staffer opened an apparent pipe bomb package found in the mailbox of Democratic donor and billionaire George Soros. Bombs were later found by U.S. Secret Service screenings of mail to Obama and Clinton.

Other packages were found addressed to former Vice President Joe Biden, California Democratic Rep. Maxine Waters, and former Attorney General Eric Holder. A package sent to former CIA Director John Brennan caused an evacuation of CNN offices in New York City.

Rep. Debbie Wasserman Schultz, D-Fla., reportedly received the package addressed to Holder. The former Democratic National Committee’s Florida office was listed as the return address on at least some of the packages, including the one sent to Brennan.

William Jonkey, a 35-year FBI veteran who worked as a special agent bomb technician, told the Washington Examiner that instructions to make proper pipe bombs are available online, but that the recently mailed devices may have had inadequate fusing systems.

"The motivation, I suspect, is political in nature. They are all Democrats, right, that have received those packages?” Jonkey said. "Somebody’s pretty sick and decided that’s what they are going to do. Other than that, who knows how these people think?”