WASHINGTON — As the Trump administration makes preparations to combat the 6,500-member Honduran migrant caravan making its way toward the United States, the Department of Homeland Security is also tracking a new caravan taking shape — this time from El Salvador, according to two U.S. officials, a local source on the ground in Central America and an internal U.S. government report obtained by NBC News.

The El Salvadoran caravan is still forming, but its members have plans to begin their journey northward toward the U.S. next week, according to the sources.

The internal report indicates that DHS is tracking the communications of caravan members, including a 230-member WhatsApp group that intends to leave on Oct. 31.

The caravan's movement is likely to trigger fierce backlash from President Donald Trump who has stoked fear about El Salvadoran migrants, particularly because nationals from the Central American country began the dangerous MS-13 gang.

However, the report indicates the early members of the caravan are immigrant families traveling with children.

It is unclear what has stoked this particular caravan to begin forming, but immigration advocates and experts believe its members may have been inspired by the Honduran caravan and hope to find safety in numbers.

Immigrants from El Salvador, Honduras and Guatemala, many of whom travel as families and claim asylum, have presented a challenge for border agents as their numbers have surged under the past two presidential administrations.

The Trump administration would like to see Central Americans be stripped of the right to remain in the United States while they pursue asylum claims, a senior administration official told reporters on a call on Tuesday. Under current law, only nationals from contiguous countries, such as Mexico, are sent back across the border without appearing before an immigration judge.

Since changing the law would require an act by Congress, which is unlikely, the Trump administration is "currently evaluating all options" to deter migrants from crossing the southern border, the official told reporters.

DHS also released new numbers on Tuesday that showed a rise in border apprehensions from August to September. Although it is normal for border crossings to rise as the weather cools, the number of migrant families was particularly high, up from 16,483 in August to 20,120 in September.

Click here for more data on border apprehensions

In total, U.S. Customs and Border Protection arrested or denied entry to 521,090 immigrants at the U.S.-Mexico border in fiscal year 2018, which ended Sept. 30, a significant jump from 415,417 the year prior.

Julia Ainsley reported from Washington. Mariana Atencio reported from Huixtla, Mexico.