WASHINGTON — A federal prisoner scheduled to be executed just days before President-elect Joe Biden takes office has tested positive for coronavirus, his lawyer said Thursday.

The Bureau of Prisons notified attorneys for Dustin John Higgs on Thursday that their client had tested positive for the virus, his attorney Devon Porter said during a court hearing Thursday afternoon.

The revelation comes amid concern about an exploding number of coronavirus cases in the federal prison system and specifically at the complex in Terre Haute, Indiana, where the executions are carried out. It is the only federal death row.

Higgs is scheduled to be executed Jan. 15, just five days before death-penalty opponent Joe Biden’s inauguration. Higgs is the last of those currently scheduled to be executed in a series of federal executions that began in July. The Trump administration will have executed more people in a single year than any other administration in more than 130 years.

Higgs’ diagnosis marks the first known coronavirus case on federal death row and raises the possibility that his execution could be delayed by a judge if his condition deteriorates. His lawyers have previously raised concerns about the possibility their client would contract the virus and could present complex health issues ahead of the execution.

The Bureau of Prisons confirmed in a statement to The Associated Press that inmates held on federal death row — known as the Special Confinement Unit — have tested positive for COVID-19.

The BOP also said a contact tracing investigation revealed that an employee working in the unit had also tested positive for the virus. It said the employee who had tested positive had no contact with any staff members involved in executions in November or December.

The agency declined to provide additional information or identify the number of inmates who have tested positive but said inmates who test positive or show symptoms will be placed in isolation.

“This is surely the result of the super spreader executions that the government has rushed to undertake in the heart of a global pandemic. Following the two executions that took place last week and one other two weeks prior, the COVID numbers at the federal prison in Terre Haute spiked enormously,” one of Higgs’ lawyers, Shawn Nolan, said in a statement. “Now our client is sick. We have asked the government to withdraw the execution date and we will ask the courts to intervene if they do not.”

As of Thursday, there were more than 300 inmates with confirmed cases of COVID-19 among inmates at FCC Terre Haute. The Bureau of Prisons said “many of these inmates are asymptomatic or exhibiting mild symptoms.”

Two other executions are scheduled at the prison complex in the days before Higgs is set to be put to death.

Higgs was convicted of ordering the 1996 murders of three women, Tamika Black, Mishann Chinn and Tanji Jackson, at a federal wildlife center near Beltsville, Maryland. Prosecutors say Higgs and two others abducted the women after Higgs became enraged because one of the women rebuffed his advances at party.

Nolan said his client didn’t kill anyone, had ineffective attorneys and didn’t deserve the death penalty. Higgs’ co-defendant, who prosecutors said carried out the killings, was not sentenced to death.