(CNN) A growing percentage of immigrants arrested by the Trump administration don't have criminal convictions on their records, even though officials have repeatedly said arresting criminals is their priority.

In the first half of fiscal year 2018, which began in October, 34% of the more than 79,000 immigrants arrested in routine operations by Immigration and Customs Enforcement were noncriminals, while 66% were convicted criminals, according to statistics released Thursday by the agency. In the same time period the previous year -- which spanned the last few months of the Obama administration and the first few months of the Trump administration -- 21% of the nearly 63,000 immigrants arrested by ICE were noncriminals and 79% were convicted criminals.

Days after being inaugurated, one of Trump's first actions was to give immigration agents wide discretion over who to go after, allowing them to target almost any undocumented immigrant as a priority.

Corey Price, assistant director for enforcement at ICE, told reporters that public safety threats and people who've committed crimes remain the focus of arrests. But the administration has broadened its approach.

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