ABC News has learned that former president Donald Trump has been indicted, according to multiple sources with knowledge. The charges were not immediately clear.

Manhattan District Attorney Alvin Bragg has notified Trump.

Trump's former attorney, Michael Cohen, said in a statement, "I do take solace in validating the adage that no one is above the law; not even a former President."

"Today’s indictment is not the end of this chapter; but rather, just the beginning," Cohen said. "Accountability matters and I stand by my testimony and the evidence I have provided to [the district attorney's office]."

The Manhattan grand jury weighing charges against former President Donald Trump will not convene on Wednesday and is expected to meet Thursday on other matters, sources familiar with the situation told ABC News.

The proceeding is conducted in secret and the grand jury could be presented with evidence or vote at any time.

David Pecker, the former publisher of the National Enquirer, was seen leaving the Manhattan District Attorney’s Office with his lawyer on Monday.

Pecker testified before the grand jury for about an hour, sources familiar with the matter told ABC News.

Pecker, who allegedly helped arrange the payment to Stormy Daniels before the 2016 election, previously spoke to the grand jury in January.

The district attorney’s office may have called Pecker to bolster Michael Cohen’s earlier testimony about the purpose of the payment.

The Manhattan grand jury weighing charges against former President Donald Trump is expected to reconvene on Monday, sources tell ABC News.

The grand jury may hear from another witness on Monday.

A white powder was discovered in the mailroom at 80 Centre Street, where the Manhattan District Attorney has offices and where a grand jury has been meeting to hear evidence in former President Donald Trump's case, according to a court official. The powder was determined to be non-hazardous, officials said.

The powder came in an envelope addressed to "Alvin," an apparent reference to Manhattan District Attorney Alvin Bragg, according police sources.

Inside the envelope was a letter containing the typewritten message, “Alvin: I am going to kill you," with 13 exclamation points, according to sources.

This envelope followed a series of unfounded threats that targeted municipal offices in New York this week.

"For three days we got four emails," Susan Stetzer, district manager at Manhattan Community Board 3, told ABC News on Friday.

At least one of the messages prompted the court to pause a hearing in the New York Attorney General’s civil lawsuit against Trump.

None of the email messages mentioned Trump by name. One included what Stetzer described as a "horrible homophobic rant."

According to Stetzer, the messages came from @mail.ru domains and some contained Cyrillic characters. The FBI is aware but does not immediately assess that the emails came from Russia, according to a law enforcement official.

"We did not get one today so I’m hoping it stops," Stetzer said.

New York City courthouses will see increased security, the Office of Court Administration said Friday.