OCALA, Fla. -

An 11th suspicious envelope was reported Wednesday in a string of suspicious package sightings in Marion County, including at six at area schools.

[PHOTOS:  Officials investigate suspicious packages in Marion County]

The Marion County Sheriff's Office said the 11th envelope was found at the Marion County Jail and contained a white powder.

A hazmat team used a specialized monitor to test the green envelope’s white, powdery content, which came back as a nonthreatening substance.

On Tuesday, in a tweet, Ocala police said suspicious packages were discovered at Lake Weir High School, West Port High School, Forest High School, Hillcrest School, the Marion County Courthouse and other locations.

"Suspicious pkgs @ MC Courthouse, LWHS, WPHS, FHS, Elks, Hillcrest, OSB - OFD, OPD & MCFR on scenes," the tweet said.

Officials later said Blessed Trinity School and Belleview High School also received suspicious packages.

Officials said a substance in a package at Lake Weir High tested negative and was found to be an artificial sweetener.  Police said that the hazardous materials team tested the Marion County courthouse and found that substance tested negative as well.

June 4 marked the last day of school in Marion County.

The Ocala Star Banner and an Elks Lodge also received suspicious packages.

According to the secretary of the Ocala Elks Lodge, the envelope had a handwritten note which stated, "Elks are devils because they donated $3,500 to the Salvation Army."

"That's what Elks do; we help organizations," Mike Mongeluzzo told Local 6's Louis Bolden.  "Whoever sent that is a very angry person."

Mongeluzzo said the green envelope was sent through U.S. mail.  He said it was postmarked from Jacksonville and had a return address.

Ocala police said that just before 4:30 p.m Tuesday, the Marion County School Board also received an envelope, bringing the total of suspicious packages to 10.

Ocala police and firefighters, along with the Marion County Sheriff's Office, continue to investigate.

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