He said that he has spoken directly with Lankan President Mahinda Rajapaksa about these pressing matters last Monday and is following up the matter with the authorities there.
"I am concerned about developments regarding internally displaced persons, the political process and a possible accountability mechanism," Ban said in response to a question during a press conference.
"I am also deeply troubled by the continued detention without charge of the two United Nations staff members," he said.
The secretary general said that this week he has sent under-secretary-general for political affairs, B Lynn Pascoe, to Sri Lanka to follow-up.
"I have asked him to deliver my letter to the president outlining the concerns of the international community and immediately report back to me," Ban said.
Pascoe was slated to visit the camps for internally displaced Tamil civilians on Thursday. Media reports from Colombo said that he will urge Colombo to speed up the release of the estimated 300,000 Tamils.
The reports quoted the envoy as saying that he would also urge the government to address allegations of human rights abuses in the fighting.
Pascoe, according to UN officials, will be holding talks on critical issues related to the aftermath of the armed conflict.
During the press conference the secretary general also talked about the internally displaced persons in Pakistan.
In response to a question whether he would attend the meeting of the Friends of Democratic Pakistan that is going to take place on the sidelines of the summit, Ban said he would certainly attend the meeting.
"You should know how committed the United Nations is, has been and will be, in ensuring the peace and stability as well as the democratization of Pakistan. That is exactly why I have appointed a Special Envoy for Humanitarian Affairs and I have also appointed a Special Adviser for these political issues," he said.
"I am encouraged that this summit-level meeting for the Group of (Friends of) Democratic Pakistan will be held on the margins of the General Assembly. Through this meeting, I would sincerely hope that they will find, first of all, political support for President Asif Ali Zardari, who has been leading his country under very difficult circumstances," he said.
Saying that Islamabad has been fighting against terrorism, Ban said that they have to establish their socio-economic development and have to also democratize their country and they the support of the UN.
"The peace and security in Pakistan has regional implications there and also the fighting against terrorism will also have regional implications: peace and security even in Afghanistan and other regional neighbours. Therefore, this will be a very important meeting," he added.