The department issued an internal memo Friday morning reminding officers to remain alert.
Here is an excerpt from that memo:
"All members of the service are reminded to think tactically and remain vigilant at all times while in uniform and should remain alert especially when members of the public approach them. Members are to always be aware of any suspicious behavior and to be alert of their surroundings, whether on or off duty."
The NYPD said it will have a security officer visible to civilians who enter any precinct, and patrols will be paired up to offer extra protection to the officers.
"All our officers will be doubled up," NYPD Commissioner William Bratton said. "Most of our patrols are usually duel. We will ensure to the best of our ability, we will double up all of our assignments. Auxiliary officers, who are unarmed with the exception of nightsticks, will not be utilized in the next several days as we get a full understanding of the circumstances in Dallas."
The killings of the five Dallas officers is not unfamiliar to the NYPD after the 2014 murders of Officers Rafael Ramos and Wenjian Liu.
"There is a combination of feelings," Bratton said. "Grief, sadness, solidarity. These events tend to bring police closer together and also bring police and community closer together. We saw that here with our own tragedies with Liu and Ramos."
The NYPD says it has received 17 threats against officers since the deaths of Alton Sterling and Philando Castile, though none has been deemed credible. The city says it expects more threats and protests, large or small, and the department will take steps to keep both officers and protesters safe.
"There will be very substantial police presence at protests, plenty of officers to keep everyone safe," Mayor Bill de Blasio said. "And we will continue to be vigilant for any information that will give us strategic change in action."
Former NYPD Commissioner Ray Kelly on keeping NYPD officers safe: