By Karen Freifeld and Sarah N. Lynch
WASHINGTON (Reuters) - U.S. Special Counsel Robert Mueller's office has spent about $3.2 million so far as part of its investigation into Russian meddling in the 2016 presidential election, the Justice Department revealed Tuesday in a report.
The expenditures took place between mid-May of this year, when the investigation began, and Sept. 30.
That money has helped fund 17 attorneys working on the probe, as well as Federal Bureau of Investigation agents, support staff, travel, rent, acquisitions of equipment and other expenses.
The bulk of the spending - $1.7 million - has been on personnel salary and benefits, according to the report.
Some of the attorneys working on the probe were hired from law firms, but many were already on the government payroll and were detailed from their regular Justice Department jobs.
Equipment acquisitions marks the second-highest expense, coming in at more than $733,000, followed by costs for rent and utilities, travel and transportation, and contractual services.
The special counsel's overall budget has not been made public.
It is unclear whether the spending by Mueller's office will be enough to prompt any outcry by Republicans who have been critical of his office.
Judicial Watch, a conservative watchdog, last month sued the Justice Department in U.S. District Court in the District of Columbia for a copy of the budget, after seeking it through a Freedom of Information Act request.
In November, several Republicans in the U.S. House of Representatives also introduced a resolution calling on Mueller to resign, saying he never disclosed to Congress the details of a bribery case involving the subsidiary of a Russian company that purchased U.S. uranium mines during his tenure as director of the FBI.
However, the resolution did not raise any concerns about Mueller's expenses.
Senator Dianne Feinstein, the top Democrat on the Senate Judiciary Committee, issued a statement Tuesday calling Mueller's spending "entirely reasonable."
Since the probe began in May, the special counsel has charged four people, two of whom have pleaded guilty.
"He should receive all the resources he needs," Feinstein said.
The $3.2 million spent only covers Mueller's probe, not the various congressional investigations of Russia's meddling in the election.
Mueller's next expense report is due at the end of March.
(Reporting by Sarah N. Lynch and Karen Freifeld; Editing by Chizu Nomiyama and Jonathan Oatis)