KABUL - A suicide bomber detonated explosives at the entrance of an upscale mall and hotel in Kabul Monday afternoon, leaving twisted metal and broken glass at a venue frequented by foreigners and wealthy Afghans.

The lunchtime blast at the newly renovated Kabul City Center shopping mall and Safi Landmark hotel killed two security guards. The guards had identified the bomber as suspicious as he approached the mall, and exchanged fire with him before the blast, said Gen. Ayoub Salangi, Kabul's police chief. Two people were wounded.

Elsewhere in Kabul, the Afghan police seized control of ballot boxes from September's disputed parliamentary election, the latest escalation of the government's attempt to prosecute voting fraud.

The explosion echoed across Kabul but caused relatively little damage to the multistory glass tower, which in addition to the hotel houses clothing, electronics and jewelry shops.

The tower's new entrance, rebuilt after a bombing last year, was a mangle of twisted metal, but upper-story windows remained intact. Carrots and apples from an adjacent juice shop were strewn on the ground, along with shards from the broken plate-glass window of a bakery. The severed head of the suicide bomber lay on the muddy sidewalk, under scraps of metal sheeting.

The violence comes less than a month after insurgents attacked the Finest supermarket in Kabul, which is located near many embassies and was popular with foreigners. The two blasts, as well as other recent attacks in Kabul, have heightened anxiety among residents that the relative calm that existed last year in the Afghan capital is being overtaken by violence.

For about two hours after the bombing, Afghan police and soldiers ran back and forth in front of the hotel, acting on rumors - which proved to be unfounded - that other potential suicide bombers had escaped into the mall and were hiding on upper floors.

There were periodic bursts of gunfire, but the target of the shots was unclear.

The Safi Landmark complex suffered worse damage last year when suicide bombers targeted Indian civilians living in a guesthouse nearby. After that blast, Hassan Razaei spent $30,000 to rebuild his bakery. On Monday, the facade of his store was destroyed again.

"I don't have a choice but to rebuild my shop," Razaei said. "The problem is nobody will come to my shop for another month. We were relying on the customers of Safi Landmark, they were shopping there and buying their cookies here."

At the headquarters of the Independent Election Commission in Kabul, Afghan police Monday took control of the data center and ballot warehouse, presumably to help a special court investigate voting fraud from the parliamentary elections.

The work of the special court has been highly controversial because many consider it an attempt by President Hamid Karzai's government to manipulate the results and install more loyal candidates.

Karzai attempted to delay seating the parliament until the investigations were completed. The elected members and Western diplomats objected, leading to a compromise in which parliament was inaugurated Jan. 26.

The IEC's chief electoral officer, Abdullah Ahmadzai, said the commission would cooperate with the special court but would not participate in any recount.

"For us, the case of the 2010 election ended with the inauguration of the national assembly," Ahmadzai said.

partlowj@washpost.com Special correspondents Habib Zahori and Javed Hamdard contributed to this report.