A former broker with Frost Bank in San Antonio, Texas, was banished from the industry on Tuesday for improperly acting as a trust officer of the bank, according to a FINRA disciplinary filing.

David Mansour "unilaterally" committed Frost Bank to serve as the successor trustee of a trust that was established for the benefit of one of Mansour's customers, FINRA alleged in the filing.

The regulator scolded Mansour for signing two documents in which he falsely represented himself as a trust officer of the bank. The documents were needed to complete a sale of mineral rights that were held by the trust to a third party, according to FINRA.

Mansour did not have the authority to sign the documents nor accept the bank's appointment as a successor trustee, FINRA said.

The regulator accused Mansour of circumventing procedures that the bank had in place for the acceptance of new trust relationships.

As a result of his actions, the bank had to return the assets which had been removed from the trust in the amount of $248,299 as part of a settlement with the trust, FINRA said.

Mansour could not be reached for comment. In his settlement with FINRA, he neither admitted nor denied the charges but consented to an entry of FINRA's findings.

FINRA also chided Mansour for failing to update his Form U4 in a timely fashion to disclose an event that occurred in October 2013. While FINRA did not specify the event in its filing, a note in his BrokerCheck report indicates that he had been charged with a misdemeanor charge of wrongful taking of property.

Mansour worked for Frost Brokerage Services from February 2001 to June 2014, when he was discharged for failing to notify the firm of a U4 disclosure event, according to BrokerCheck records.

Bill Day, a spokesman for Frost Bank, had no comment beyond what is publicly available through FINRA.