"There are question that, ultimately, only the chancellor can answer," parliamentary committee chairman Rainer Arnold, from the Social Democrats (SPD), told German daily newspaper Bild on Saturday, March 27.

Arnold was echoing calls by members of the Green and Left parties, who said on Friday that the chancellor should testify before the committee.

The demands come after reports earlier in the week that the chancellor's office had received information that civilians had been killed in a German-ordered airstrike in Afghanistan within hours of the event taking place in September 2009.

Much of the parliamentary inquiry is focused on who knew what about the bombing and whether knowledge of civilian casualties was kept quiet.

E-mail sent to Merkel's office

The German news weekly Der Spiegel reported on Thursday that the country's foreign intelligence service (BND) sent an e-mail about the attack and causalities to Merkel's office.

"Many civilians were killed (numbers vary between 50 and 100)," the email was reported to have read.

A spokesman for the government said that the e-mail had been an unconfirmed preliminary report and that the message content had already been handed over to the parliamentary investigation.

In addition to Arnold's comments, SPD parliamentary speaker Thomas Oppermann said that the chancellor should have done more, and sooner, to explain the nature of injuries and fatalities caused by the biggest attack involving German troops since the Second World War.

Claims of electioneering

But Andreas Schockenhoff, the conservative parliamentary group's vice chairman, rejected the criticism and accused the SPD of electioneering tactics ahead of regional voting in the state of North Rhine-Westphalia.

"The claim that Angela Merkel has not been open about Kunduz and its consequences is malicious," Schockenhoff told the German newspaper Frankfurter Allgemeine Sonntagszeitung.

The parliamentary investigation aims to clarify events before and after German Colonel Georg Klein ordered an airstrike on two hijacked fuel tankers. Up to 142 people were killed in the strike, including, it is believed, dozens of civilians.

The incident led to a political storm in Germany, claiming the jobs of the former minister of defense, Franz Josef Jung, and Gemany's top military officer, Wolfgang Schneiderhan.

rc/dpa/AFP/Reuters/AP

Editor: Toma Tasovac