A suicide bomber struck Monday near the Russian embassy in the Afghan capital Kabul, killing two staff from the diplomatic mission and four others. In the first attack targeting a foreign mission since the Taliban seized power in August last year, the bomber struck near the entrance of the embassy’s consular section. “Without any doubt, we are talking about a terrorist act, which is absolutely unacceptable,” Kremlin spokesman Dmitry Peskov told journalists in Moscow. Afghanistan’s foreign ministry confirmed the deaths of two embassy staff. Four Afghans waiting for consular services were also killed and several more wounded, Kabul police said. Violence in Afghanistan has largely declined since the Taliban returned to power, but several bomb blasts — some targeting minority communities — have rocked the country in recent months, many claimed by the jihadist Islamic State (IS) group. As with other recent attacks, heavy Taliban security quickly sealed off the area and prevented media from filming nearby. No group has so far claimed the attack on the diplomatic mission. Russian Foreign Minister Sergei Lavrov said immediate steps were taken to boost security at the embassy, located on one of Kabul’s main roads and leading to the parliament building. The attack is sure to embarrass the Taliban leadership, which for months has encouraged foreign nations to reopen their Kabul missions, insisting security was guaranteed.