A plan to arrest more than 2,000 immigrants with final deportation orders across the country is off to a slow start with just 35 arrests so far, federal officials said Tuesday.

The operation -- touted by President Trump on Twitter -- may have been slowed by intense media focus and advocates who took to social media and went into immigrant neighborhoods to notify undocumented immigrants of their legal rights to avoid arrest.

Some attempted arrests were called off for the safety of the immigration agents, Matthew Albence, the acting head of the Immigration and Customs Enforcement, said in a call with reporters.

“We had instances where we had officers who believed they were being surveilled,” Albence said.

However, he said the operation will continue for an unspecified period and more than 2,000 immigrants living in the country illegally remain on the list of targets. All of the targeted immigrants have final deportation orders and have gone through an expedited court process.

“We’re patient and we’ll continue to pursue these cases,” Albence said.

ICE declined to say the states or cities where the 35 people were arrested or whether there were any plans for additional arrests in New Jersey.

Of the 35 people arrested, 18 were part of family units and 17 were “collateral” arrests, meaning they were picked up in connection with the operation but were not among those originally targeted, federal officials said.

Albence objected strongly to using the term “raids" to describe the operation, saying the word evokes negative emotions and is not accurate because the arrests focused on individuals who had final deportation orders.

The operation, which was scheduled to begin around July 14, was expected to target several large cities, including: Atlanta, Baltimore, Chicago, Denver, Los Angeles, Miami, New York and San Francisco.

ICE officials said they took New Orleans off the list because Tropical Storm Barry had hit the area that weekend.

It is unclear if any of the operations targeted New Jersey during the first weekend. In Passaic, a teenager said she woke up around 1 a.m. to what she believed to be ICE agents knocking on her door. But she refused to answer after seeing a “know your rights” post on Instagram.

She said she also refused to allow ICE entry when they returned a few hours later in the early morning.

A spokesman for ICE’s Newark office denied agents went to the Passaic house and said agents do not typically make arrests before 6 a.m.

Sara Cullinane, director of the immigrant advocacy group Make the Road New Jersey, questioned ICE’s denial.

“ICE is a notoriously non-transparent agency with a long record of violating constitutional rights,” Cullinane said at the time.

In New York, Mayor Bill de Blasio’s office said there were three unsuccessful attempts by ICE to detain individuals in East Harlem and Sunset Park during the first weekend of the operation. But no arrests were made.

In some cases, immigrants said they believed they avoided arrest by asking ICE agents if they had a court warrant, then refusing to answer the door if the officers could not produce the document.

ICE did not release any information about the 35 people arrested or the status of their cases. Albence said he was not aware of any arrested families in which children were separated from their parents while in ICE custody.

However, he said all of the 2,000 targeted families had previously been given a chance to avoid arrest.

“We gave these families, back in February, an opportunity to turn themselves in,” Albence said.

Nationwide, there are about 1 million immigrants living in the country illegally with final deportation orders that have not been enforced, ICE officials said.

Kelly Heyboer may be reached at kheyboer@njadvancemedia.com. Follow her on Twitter @KellyHeyboer. Find her at KellyHeyboerReporter on Facebook. Find NJ.com on Facebook.

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