UPDATED | November 17, 2015 11:57 AM

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DALLAS (CBSDFW.COM) – “Obviously someone is trying to scare Dallas and that’s not going to work.” Those words from Dallas Mayor Mike Rawlings this morning after the Dallas Independent School District received a terroristic threat Wednesday evening. that was similar to the warnings levied against school districts in Los Angeles and New York earlier this week.

During a morning press conference Superintendent Michael Hinojosa explained, “Last evening, about 8 o’clock, some staff members got some information they thought it was important to share with us.” It was then that several Dallas ISD staff members received a threat via email. Most of the individuals receiving the email were teachers at Pinkston High and Martinez Elementary School.

Sources say the threat claimed to have explosives that would be detonated in a coordinated effort. The sender reportedly defined himself as a Muslim, who needed to “punish non-believers.”

After receiving the email district officials were notified and DISD police activated their “emergency response protocol.” DISD Police Chief Craig Miller said, “We took that information very seriously.”

The district police department worked with Dallas police and other law enforcement agencies to verify that Pinkston High, Martinez Elementary and every other school in the district was safe.

Miller said, “By 11:20 last night we were at those schools with bomb dogs and a task force supplied by the DPD.” The canines assisted with sweeps at both Pinkston and Martinez. It was at 2:20 a.m. when Dallas police officially determined that the threat was not credible and released the buildings back to the district.

Mayor Rawlings expressed his gratitude to those who worked to verify and rectify the situation. “We knew something like this might happen, that’s why these professionals train and work together with our joint task force. We put that [team] into action last night and we are able to say to the students of those schools, ‘Go to school, it’s safe.’”

As for what lies ahead Mayor Rawlings was clear. “Throughout the next few days you’ll be hearing and seeing more of this, but I think it’s important to know that the teams work together and we are a safe city this morning, but we’re going to make sure that we are vigilant and these guys are going to be working overtime in our schools and throughout our city.”

Superintendent Hinojosa agreed saying, “I think that everyone has done their due diligence on the information that we have. We feel that our students are safe, but it was very important that we take assertive action at this point.”

DISD officials say they remain in contact with Dallas police as well as the Joint Terrorism Task Force and are conducting an ongoing investigation of the threat.

Dallas police Chief David Brown said they are doing everything they can to determine the source of the emails. “We’re trying as best we can to understand how we track through the IP address to get the source of these threats. We haven’t identified any suspicious people or persons in the area associated with this email threat, but we are pursuing every lead.”

When received, those leads could result in arrests and possible jail time for the person/persons involved. “The terroristic threat designation is a criminal offense in the State of Texas and that’s what we’re utilizing to proceed in our investigative inquiry,” said Brown.

Brown went on to say that despite the possible outcomes in situations like this, Dallas residents must press on.

“As we go forward we need to make sure that we don’t overacted to fear. This is not necessarily just a hoax that we are discounting… we have to take this threat seriously and we have to pursue any and all leads to hold someone accountable.”

There will be an increased presence, by both Dallas ISD Police and the Dallas Police Department, in and around campuses today and tomorrow. Friday is the last day of classes before students leave for winter break. Officials said their number one priority is the safety of students and staff.

Superintendent Hinojosa said parents were contacted through the district robocall messaging system and that they relayed as much information as possible to reassure them and encourage that students and staff keep their normal schedule. “Today is testing day at our secondary schools. We want our students to be here. We want, like the Mayor said, we want to continue on with business as usual.”

So far, there have been no reports as to if attendance is up or down today, but administrators said they expect “our students to show up.”

Sometime during or after the threat was made against the DISD, the district learned that a same or similar email was sent to staff in the Houston ISD and Miami Public Schools in Florida.

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