HONOLULU -- The prosecution presented more evidence on Thursday that murder defendant Kirk Lankford tried to cover his tracks the day Masumi Watanabe disappeared last year.

Watanabe disappeared at about 9:30 a.m. last April 12. That is about the time when Lankford had about an hour and a half between pest control jobs.

The prosecutor revealed on Thursday Lankford clumsily altered documents to make his free time seem an hour shorter and the jobs longer.

"So how long does this suggest he has been at Mr. Wyngate's house," City Prosecutor Peter Carlisle asked pointing to a document on a video screen.

"An hour and 15 minutes," a Hauoli Pest Control supervisor said.

"Would that be unusual for a regular service?"

"Yes that could be," the supervisor said.

Another supervisor drew a diagram to show windshield damage from that day, which Lankford blamed on a bird. Because of his explanation the windshield was quickly repaired and not saved for investigators.

The supervisor also noticed something different about the inside of Lankford's truck.

"The interior of his truck was clean," supervisor David Patacsil said.

"And is that unusual?" Carlisle asked.

"Yes for Kirk. Yes. Usually his truck had a lot of rubbish in it," Patacsil said.

The altered records, the damaged windshield and the scrubbed truck, which still revealed evidence of Watanabe's blood, seem to make a strong case against Lankford despite the fact Watanabe's body has never been found, KITV reported.

Although there have been some hints, Lankford's defense attorney has refused to reveal his strategy, and that made tempers flare as each side accused the other of planning an ambush.

Lankford may claim that he accidentally hit Watanabe and covered up her death to save his $75,000-a-year job.