The Department of Justice is requesting more details about the proposed sale of Charleston’s ABC television station in a move that’s likely to delay and complicate the deal.

The federal agency’s “second request” for information stems from an antitrust review in connection with the transaction.

Sinclair Broadcast Group Inc. wants to buy WCIV-TV 4 in Mount Pleasant from Perpetual Corp., the parent company of station owner Allbritton Communications Co.

Sinclair and Allbritton said in a joint statement this week they “intend to respond promptly” to Justice’s request.

“Although there can be no assurances, the parties expect the transaction to close in the first or second quarter of 2014,” they said.

When the deal was announced in late July, Sinclair said it hoped to finalize it by the end of 2013.

The Federal Communications Commission also must approve the sale.

Sinclair agreed to pay Allbritton $985 million for WCIV and six other ABC stations, along with a cable outlet in Washington, D.C..

If the deal goes through, Sinclair would own WCIV outright and control WTAT-TV 24, the local Fox affiliate, through a closely affiliated business.

Furthermore, the company has said it plans to continue running a third Charleston station it now owns is planning to sell, WMMP-TV, under a deal with the buyer. Sinclair has owned the local MyNetworkTV carrier since 1998.

The broadcaster is drawing fire because of its use of affiliated “sidecar” businesses to get around federal rules that prohibit one company from owning multiple TV stations in markets like Charleston. That tactic has enabled the Maryland company to expand into a powerhouse.

Sinclair said in a filing with the FCC all of the agreements in the Allbritton deal “are squarely within the boundaries of what the commission has repeatedly approved in the past,”

The purchase has triggered opposition, including a protest to the FCC from a national trade organization representing small and midsized cable TV companies.

The American Cable Association said last month that the sale “will reduce competition and harm consumers.”

It said its members would be harmed because the local Fox and ABC stations could work together when negotiating retransmission fees Sinclair charges cable and satellite TV providers.

The proposed purchase of a Pennsylvania station also is singled out in the protest.

“Under FCC rules, the ... ownership of more than one of the four most highly rated stations in a local market — typically, the affiliates of ABC, CBS, NBC and Fox — is prohibited,” the association said.

The group is asking the FCC to either deny the sale or impose conditions to prevent the Sinclair stations from colluding on retransmission fees.

Justice’s antitrust division could not be reached for comment this week. It’s closed because of the partial government shutdown.