SPOKANE - The newly appointed president of the NAACP said Friday that the local chapter is still interested in finding out who mailed the threatening letters to the organization, but police say they have exhausted all leads.

Naima Quarles-Burnley, who announced during a press conference in Spokane on Friday that she is now the Spokane chapter president, said police were investigating three mailings that occurred between February and May of this year.

The Spokesman Review reported on Friday that the NAACP received another letter, dated June 15, which they suspect came from the same person.

On Monday the local chapter of the NAACP issued a press release calling on the police and the U.S. Postal Service to fully disclose their findings in the "hate mail" cases, and to fully investigate all three mailings.

"The Spokane NAACP is requesting that the Spokane Police Department, the USPS and other agencies involved give full disclosure of the findings, conclusions, and ongoing investigations related to the 'Hate Mail' received at the Spokane NAACP mailboxes and related incidents. Further, we call upon law enforcement to actively pursue all three 'Hate Mail' incidences reported."

Burnley said Friday that the Spokane Police Department did respond to that request and will provide the organization with all of the police reports regarding the investigation.

She said members wonder why police stopped the investigation after determining the only way the February letter that was sent to the NAACP post office box could have been placed there is by someone with a key to the box.

Police suspended their investigation into the mailings the day The Press broke a story detailing how Rachel Dolezal masqueraded as an African-American woman as she rose to positions of power in Spokane.

Police released detailed reports of the investigation, which provided some answers but also raised some questions.

While police were able to rule out a handwritten letter mentioning Dolezal that was sent on May 4 to the mayor of Spokane and others as unrelated, the origin of the other two letters is still a mystery.

A 17-page letter that was found in the NAACP's Rosewood P.O. box on Feb. 25 was addressed to the organization, with Dolezal's name highlighted in a line under the address.

Police determined that letter was never mailed through the postal system because it was never barcoded or postmarked and the stamps were never canceled.

SPD Detective Brian Cestnik investigated the letter and quickly ruled out all of the postal workers who would have had access to the post office box without a key.

"I have now spoken to every U.S. Post Office employee who had access to the NAACP mail box in the week and half prior to the letter being reported found," he wrote in a report dated March 26. "I do not have any reason to believe that any of these employees were involved in putting the letter in this box."

Cestnik concluded that someone with a key had to have placed the letter in the post office box, according to the report.

The detective also found that only two keys were ever issued for that box. NAACP members said that typically the president and the secretary carry those keys.

According to SPD spokeswoman Teresa Fuller, Dolezal told Cestnik that she possessed one of the keys and the other one was lost.

"So anyone could have that key," Fuller said. "Like I said before, we have exhausted all of the leads in this investigation."

However there is still a question about several letters that were mailed to several community leaders in Spokane on May 6 that appear to have come from the same person who mailed the February letter, according to the reports.

The June 15 letter received by the Spokesman Review also appeared to be from the same writer and all of those letters were postmarked from Oakland, Calif.

Dolezal was in Oakland shortly before the February letter was sent and had other ties to the Bay Area, but Cestnik's reports that were released to the media do not address the letters.

Cestnik's reports only included photocopies of the letter that was sent and the envelopes but they do not include any narrative of the investigation.

Fuller said she contacted Cestnik, who was off work Friday, and he told her he filed reports on the Oakland letters.

"Brian just confirmed with me that those reports do exist," Fuller said. "I will track those down on Monday and send them to you."